CS-Notes/notes/2016 校招真题题解.md

<!-- GFM-TOC -->
* [ǰ<EFBFBD><EFBFBD>](#ǰ<><C7B0>)
* [1. С<><D0A1>-С<><D0A1>Git](#1-С<><D0A1>-С<><D0A1>git)
* [2. С<><D0A1>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#2-С<><D0A1>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
* [3. С<><D0A1>-<2D>й<EFBFBD>ţ<EFBFBD><C5A3>](#3-С<><D0A1>-<2D>й<EFBFBD>ţ<EFBFBD><C5A3>)
* [4. ΢<><CEA2>-LUCKY STRING](#4-΢<><CEA2>-lucky-string)
* [5. ΢<><CEA2>-Numeric Keypad](#5-΢<><CEA2>-numeric-keypad)
* [6. ΢<><CEA2>-Spring Outing](#6-΢<><CEA2>-spring-outing)
* [7. ΢<><CEA2>-S-expression](#7-΢<><CEA2>-s-expression)
* [8. <20><>Ϊ-<2D><><EFBFBD>߷<EFBFBD><DFB7>Ƕ<EFBFBD><C7B6><EFBFBD>](#8-<2D><>Ϊ-<2D><><EFBFBD>߷<EFBFBD><DFB7>Ƕ<EFBFBD><C7B6><EFBFBD>)
* [9. <20><>Ϊ-<2D>򵥴<EFBFBD><F2B5A5B4><EFBFBD><EFBFBD><EFBFBD>¼](#9-<2D><>Ϊ-<2D>򵥴<EFBFBD><F2B5A5B4><EFBFBD><EFBFBD><EFBFBD>¼)
* [10. <20><>Ϊ-<2D>˿<EFBFBD><CBBF>ƴ<EFBFBD>С](#10-<2D><>Ϊ-<2D>˿<EFBFBD><CBBF>ƴ<EFBFBD>С)
* [11. ȥ<>Ķ<EFBFBD>-<2D><><EFBFBD>ֲ<EFBFBD><D6B2><EFBFBD>](#11-ȥ<>Ķ<EFBFBD>-<2D><><EFBFBD>ֲ<EFBFBD><D6B2><EFBFBD>)
* [12. ȥ<>Ķ<EFBFBD>-<2D>׸<EFBFBD><D7B8>ظ<EFBFBD><D8B8>ַ<EFBFBD>](#12-ȥ<>Ķ<EFBFBD>-<2D>׸<EFBFBD><D7B8>ظ<EFBFBD><D8B8>ַ<EFBFBD>)
* [13. ȥ<>Ķ<EFBFBD>-Ѱ<><D1B0>Coder](#13-ȥ<>Ķ<EFBFBD>-Ѱ<><D1B0>coder)
* [14. <20><><EFBFBD><EFBFBD>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ](#14-<2D><><EFBFBD><EFBFBD>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ)
* [15. <20><><EFBFBD><EFBFBD>-<2D><><EFBFBD>ӷ<EFBFBD>ת](#15-<2D><><EFBFBD><EFBFBD>-<2D><><EFBFBD>ӷ<EFBFBD>ת)
* [16. <20><><EFBFBD><EFBFBD>-<2D>ݷ<EFBFBD>](#16-<2D><><EFBFBD><EFBFBD>-<2D>ݷ<EFBFBD>)
* [17. <20><><EFBFBD><EFBFBD>-ֱ<><D6B1>ͼ<EFBFBD><CDBC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#17-<2D><><EFBFBD><EFBFBD>-ֱ<><D6B1>ͼ<EFBFBD><CDBC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
* [18. <20><><EFBFBD><EFBFBD>-<2D>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#18-<2D><><EFBFBD><EFBFBD>-<2D>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
* [19. <20><><EFBFBD><EFBFBD>-ƽ<><C6BD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#19-<2D><><EFBFBD><EFBFBD>-ƽ<><C6BD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
* [20. <20>ٶ<EFBFBD>-<2D>ﷸת<EFB7B8><D7AA>](#20-<2D>ٶ<EFBFBD>-<2D>ﷸת<EFB7B8><D7AA>)
* [22. <20>ٶ<EFBFBD>-<2D>ü<EFBFBD><C3BC><EFBFBD><EFBFBD><EFBFBD>ֽ](#22-<2D>ٶ<EFBFBD>-<2D>ü<EFBFBD><C3BC><EFBFBD><EFBFBD><EFBFBD>ֽ)
* [23. <20>ٶ<EFBFBD>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>](#23-<2D>ٶ<EFBFBD>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>)
* [24. <20>ٶ<EFBFBD>-Ģ<><C4A2><EFBFBD><EFBFBD>](#24-<2D>ٶ<EFBFBD>-Ģ<><C4A2><EFBFBD><EFBFBD>)
<!-- GFM-TOC -->

# ǰ<><C7B0>

ʡ<EFBFBD>ԵĴ<EFBFBD><EFBFBD>룺

```java
import java.util.*;
```

```java
public class Solution {
}
```

```java
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNext()) {
        }
    }
}
```

# 1. С<><D0A1>-С<><D0A1>Git

- <20>ؽ<EFBFBD><D8BD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
- ʹ<><CAB9> LCA

```java
private class TreeNode {
    int id;
    List<TreeNode> childs = new ArrayList<>();

    TreeNode(int id) {
        this.id = id;
    }
}

public int getSplitNode(String[] matrix, int indexA, int indexB) {
    int n = matrix.length;
    boolean[][] linked = new boolean[n][n]; // <20>ؽ<EFBFBD><D8BD>ڽӾ<DABD><D3BE><EFBFBD>
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) {
            linked[i][j] = matrix[i].charAt(j) == '1';
        }
    }
    TreeNode tree = constructTree(linked, 0);
    TreeNode ancestor = LCA(tree, new TreeNode(indexA), new TreeNode(indexB));
    return ancestor.id;
}

private TreeNode constructTree(boolean[][] linked, int root) {
    TreeNode tree = new TreeNode(root);
    for (int i = 0; i < linked[root].length; i++) {
        if (linked[root][i]) {
            linked[i][root] = false; //  <20><>Ϊ<EFBFBD><CEAA>Ŀ<EFBFBD><C4BF><EFBFBD><EFBFBD><EFBFBD>ڽӾ<DABD><D3BE><EFBFBD><EFBFBD><EFBFBD>˫<EFBFBD><CBAB><EFBFBD>ģ<EFBFBD><C4A3><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><D2AA><EFBFBD><EFBFBD>תΪ<D7AA><CEAA><EFBFBD><EFBFBD><EFBFBD><EFBFBD>
            tree.childs.add(constructTree(links, i));
        }
    }
    return tree;
}

private TreeNode LCA(TreeNode root, TreeNode p, TreeNode q) {
    if (root == null || root.id == p.id || root.id == q.id) return root;
    TreeNode ancestor = null;
    int cnt = 0;
    for (int i = 0; i < root.childs.size(); i++) {
        TreeNode tmp = LCA(root.childs.get(i), p, q);
        if (tmp != null) {
            ancestor = tmp;
            cnt++;
        }
    }
    return cnt == 2 ? root : ancestor;
}
```

# 2. С<><D0A1>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>򣬽<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ķ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ʊ<EFBFBD>ʾΪ 1 <20><><EFBFBD><EFBFBD>һλ<D2BB><CEBB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><CDAC>λ<EFBFBD><CEBB>

```java
public int countBitDiff(int m, int n) {
    return Integer.bitCount(m ^ n);
}
```

# 3. С<><D0A1>-<2D>й<EFBFBD>ţ<EFBFBD><C5A3>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>⣬<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>СΪ 2 <20>ı<EFBFBD><C4B1><EFBFBD><EFBFBD><EFBFBD>

״̬ת<EFBFBD>Ʒ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>£<EFBFBD>

```html
dp[i, j] = max(dp[i, j-1], prices[j] - prices[jj] + dp[i-1, jj]) { jj in range of [0, j-1] } = max(dp[i, j-1], prices[j] + max(dp[i-1, jj] - prices[jj]))
```

```java
public int calculateMax(int[] prices) {
    int n = prices.length;
    int[][] dp = new int[3][n];
    for (int i = 1; i <= 2; i++) {
        int localMax = dp[i - 1][0] - prices[0];
        for (int j = 1; j < n; j++) {
            dp[i][j] = Math.max(dp[i][j - 1], prices[j] + localMax);
            localMax = Math.max(localMax, dp[i - 1][j] - prices[j]);
        }
    }
    return dp[2][n - 1];
}
```

# 4. ΢<><CEA2>-LUCKY STRING

- 쳲<><ECB3B2><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>п<EFBFBD><D0BF><EFBFBD>Ԥ<EFBFBD><D4A4><EFBFBD>㣻
- <20><>ͷ<EFBFBD><CDB7>β<EFBFBD><CEB2><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD>Ĺ<EFBFBD><C4B9>̣<EFBFBD>ÿһ<C3BF><D2BB>ѭ<EFBFBD><D1AD><EFBFBD><EFBFBD>ʹ<EFBFBD><CAB9>һ<EFBFBD><D2BB> Set <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> i <20><> j <20><><EFBFBD>ֵ<EFBFBD><D6B5>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> Set <20><>֤<EFBFBD><D6A4><EFBFBD>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD>ͬ<EFBFBD><CDAC><EFBFBD><EFBFBD><EFBFBD><EFBFBD> Set <20>Ĵ<EFBFBD>С<EFBFBD><D0A1><EFBFBD>Dz<EFBFBD>ͬ<EFBFBD>ַ<EFBFBD><D6B7>ĸ<EFBFBD><C4B8><EFBFBD><EFBFBD><EFBFBD>

```java
Set<Integer> fibSet = new HashSet<>(Arrays.asList(1, 2, 3, 5, 8, 13, 21, 34, 55, 89));
Scanner in = new Scanner(System.in);
String str = in.nextLine();
int n = str.length();
Set<String> ret = new HashSet<>();
for (int i = 0; i < n; i++) {
    Set<Character> set = new HashSet<>();
    for (int j = i; j < n; j++) {
        set.add(str.charAt(j));
        int cnt = set.size();
        if (fibSet.contains(cnt)) {
            ret.add(str.substring(i, j + 1));
        }
    }
}
String[] arr = ret.toArray(new String[ret.size()]);
Arrays.sort(arr);
for (String s : arr) {
    System.out.println(s);
}
```

# 5. ΢<><CEA2>-Numeric Keypad

```java
private static int[][] canReach = {
        {1, 0, 0, 0, 0, 0, 0, 0, 0, 0}, // 0
        {1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, // 1
        {1, 0, 1, 1, 0, 1, 1, 0, 1, 1}, // 2
        {0, 0, 0, 1, 0, 0, 1, 0, 0, 1}, // 3
        {1, 0, 0, 0, 1, 1, 1, 1, 1, 1}, // 4
        {1, 0, 0, 0, 0, 1, 1, 0, 1, 1}, // 5
        {0, 0, 0, 0, 0, 0, 1, 0, 0, 1}, // 6
        {1, 0, 0, 0, 0, 0, 0, 1, 1, 1}, // 7
        {1, 0, 0, 0, 0, 0, 0, 0, 1, 1}, // 8
        {0, 0, 0, 0, 0, 0, 0, 0, 0, 1}  // 9
};

private static boolean isLegal(char[] chars, int idx) {
    if (idx >= chars.length || idx < 0) return true;
    int cur = chars[idx] - '0';
    int next = chars[idx + 1] - '0';
    return canReach[cur][next] == 1;
}

public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    int T = Integer.valueOf(in.nextLine());
    for (int i = 0; i < T; i++) {
        String line = in.nextLine();
        char[] chars = line.toCharArray();
        for (int j = 0; j < chars.length - 1; j++) {
            while (!isLegal(chars, j)) {
                if (--chars[j + 1] < '0') {
                    chars[j--]--;
                }
                for (int k = j + 2; k < chars.length; k++) {
                    chars[k] = '9';
                }
            }
        }
        System.out.println(new String(chars));
    }
}
```

# 6. ΢<><CEA2>-Spring Outing

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> N = 3<><33>K = 4 <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ۡ<EFBFBD>

<EFBFBD><EFBFBD>ʼʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 0 <20><><EFBFBD>ط<EFBFBD><D8B7><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD><EFBFBD>ص㣬Ҳ<E3A3AC><D2B2><EFBFBD>Ǵ<EFBFBD><C7B4>ڼ<EFBFBD><DABC>

<EFBFBD>ӵ<EFBFBD> 4 <20><><EFBFBD>ص㿪ʼͶƱ<CDB6><C6B1>ÿ<EFBFBD><C3BF><EFBFBD><EFBFBD>ֻ<EFBFBD><D6BB>Ҫ<EFBFBD>Ƚϵ<C8BD> 4 <20><><EFBFBD>ط<EFBFBD><D8B7>͵<EFBFBD> 0 <20><><EFBFBD>ط<EFBFBD><D8B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȼ<EFBFBD><C8BC><EFBFBD><EFBFBD><EFBFBD><EFA3AC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ѡ<EFBFBD><D1A1><EFBFBD>˵<EFBFBD> 4 <20><><EFBFBD>ط<EFBFBD><D8B7><EFBFBD><EFBFBD><EFBFBD>ô<EFBFBD><C3B4><EFBFBD>µ<EFBFBD> 4 <20><><EFBFBD>ط<EFBFBD><D8B7><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD><EFBFBD>ص㡣

<EFBFBD>Ӻ<EFBFBD><EFBFBD><EFBFBD>ǰ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ظ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ϲ<EFBFBD><EFBFBD>裬<EFBFBD><EFBFBD><EFBFBD>ϸ<EFBFBD><EFBFBD>´<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ص㣬ֱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>еط<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ѿ<EFBFBD>ͶƱ<EFBFBD><EFBFBD>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>У<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 0 <20><><EFBFBD>ص<EFBFBD><D8B5><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD><EFBFBD>ص㣬<D8B5><E3A3AC><EFBFBD><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD><EFBFBD>Ļ<EFBFBD><C4BB><EFBFBD> 4 <20><><EFBFBD>ص<EFBFBD><D8B5><EFBFBD>ֻ<EFBFBD><D6BB>Ҫ<EFBFBD><D2AA><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ص<EFBFBD><D8B5><EFBFBD><EFBFBD>бȽϣ<C8BD><CFA3><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ÿ<EFBFBD><C3BF><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʼ<EEBFAA><CABC><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 1 <20><><EFBFBD>ص<EFBFBD><D8B5><EFBFBD>Ϊ<EFBFBD><CEAA><EFBFBD><EFBFBD><EFBFBD>ص㣬<D8B5><E3A3AC>ô<EFBFBD>ڶԵ<DAB6> 2 <20><><EFBFBD>ص<EFBFBD><D8B5><EFBFBD><EFBFBD><EFBFBD>ͶƱʱ<C6B1><CAB1>ÿ<EFBFBD><C3BF><EFBFBD>˲<EFBFBD><CBB2><EFBFBD>Ҫ<EFBFBD><D2AA><EFBFBD>ǵ<EFBFBD> 2 <20><><EFBFBD>ص<EFBFBD><D8B5><EFBFBD><EFBFBD><EFBFBD> 1 <20><><EFBFBD>ص<EFBFBD><D8B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȼ<EFBFBD><C8BC><EFBFBD>ҲҪ<D2B2><D2AA><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ͶƱ<CDB6>ص<EFBFBD><D8B5><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȼ<EFBFBD><C8BC><EFBFBD>

```java
int N = in.nextInt();
int K = in.nextInt();
int[][] votes = new int[N][K + 1];
for (int i = 0; i < N; i++) {
    for (int j = 0; j < K + 1; j++) {
        int place = in.nextInt();
        votes[i][place] = j;
    }
}
int ret = 0;
for (int place = K; place > 0; place--) {
    int cnt = 0;
    for (int i = 0; i < N; i++) {
        if (votes[i][place] < votes[i][ret]) {
            cnt++;
        }
    }
    if (cnt > N / 2) {
        ret = place;
    }
}
System.out.println(ret == 0 ? "otaku" : ret);
```

# 7. ΢<><CEA2>-S-expression

# 8. <20><>Ϊ-<2D><><EFBFBD>߷<EFBFBD><DFB7>Ƕ<EFBFBD><C7B6><EFBFBD>

```java
int N = in.nextInt();
int M = in.nextInt();
int[] scores = new int[N];
for (int i = 0; i < N; i++) {
    scores[i] = in.nextInt();
}
for (int i = 0; i < M; i++) {
    String str = in.next();
    if (str.equals("U")) {
        int id = in.nextInt() - 1;
        int newScore = in.nextInt();
        scores[id] = newScore;
    } else {
        int idBegin = in.nextInt() - 1;
        int idEnd = in.nextInt() - 1;
        int ret = 0;
        if (idBegin > idEnd) {
            int t = idBegin;
            idBegin = idEnd;
            idEnd = t;
        }
        for (int j = idBegin; j <= idEnd; j++) {
            ret = Math.max(ret, scores[j]);
        }
        System.out.println(ret);
    }
}
```

# 9. <20><>Ϊ-<2D>򵥴<EFBFBD><F2B5A5B4><EFBFBD><EFBFBD><EFBFBD>¼

```java
HashMap<String, Integer> map = new LinkedHashMap<>();
while (in.hasNextLine()) {
    String s = in.nextLine();
    String key = s.substring(s.lastIndexOf('\\') + 1);
    map.put(key, map.containsKey(key) ? map.get(key) + 1 : 1);
}
List<Map.Entry<String, Integer>> list = new LinkedList<>(map.entrySet());
Collections.sort(list, (o1, o2) -> o2.getValue() - o1.getValue());
for (int i = 0; i < 8 && i < list.size(); i++) {
    String[] token = list.get(i).getKey().split(" ");
    String filename = token[0];
    String line = token[1];
    if (filename.length() > 16) filename = filename.substring(filename.length() - 16);
    System.out.println(filename + " " + line + " " + list.get(i).getValue());
}
```

# 10. <20><>Ϊ-<2D>˿<EFBFBD><CBBF>ƴ<EFBFBD>С

```java
public class Main {

    private Map<String, Integer> map = new HashMap<>();

    public Main() {
        map.put("3", 0);
        map.put("4", 1);
        map.put("5", 2);
        map.put("6", 3);
        map.put("7", 4);
        map.put("8", 5);
        map.put("9", 6);
        map.put("10", 7);
        map.put("J", 8);
        map.put("Q", 9);
        map.put("K", 10);
        map.put("A", 11);
        map.put("2", 12);
        map.put("joker", 13);
        map.put("JOKER ", 14);
    }

    private String play(String s1, String s2) {
        String[] token1 = s1.split(" ");
        String[] token2 = s2.split(" ");
        CardType type1 = computeCardType(token1);
        CardType type2 = computeCardType(token2);
        if (type1 == CardType.DoubleJoker) return s1;
        if (type2 == CardType.DoubleJoker) return s2;
        if (type1 == CardType.Bomb && type2 != CardType.Bomb) return s1;
        if (type2 == CardType.Bomb && type1 != CardType.Bomb) return s2;
        if (type1 != type2 || token1.length != token2.length) return "ERROR";
        for (int i = 0; i < token1.length; i++) {
            int val1 = map.get(token1[i]);
            int val2 = map.get(token2[i]);
            if (val1 != val2) return val1 > val2 ? s1 : s2;
        }
        return "ERROR";
    }

    private CardType computeCardType(String[] token) {
        boolean hasjoker = false, hasJOKER = false;
        for (int i = 0; i < token.length; i++) {
            if (token[i].equals("joker")) hasjoker = true;
            else if (token[i].equals("JOKER")) hasJOKER = true;
        }
        if (hasjoker && hasJOKER) return CardType.DoubleJoker;
        int maxContinueLen = 1;
        int curContinueLen = 1;
        String curValue = token[0];
        for (int i = 1; i < token.length; i++) {
            if (token[i].equals(curValue)) curContinueLen++;
            else {
                curContinueLen = 1;
                curValue = token[i];
            }
            maxContinueLen = Math.max(maxContinueLen, curContinueLen);
        }
        if (maxContinueLen == 4) return CardType.Bomb;
        if (maxContinueLen == 3) return CardType.Triple;
        if (maxContinueLen == 2) return CardType.Double;
        boolean isStraight = true;
        for (int i = 1; i < token.length; i++) {
            if (map.get(token[i]) - map.get(token[i - 1]) != 1) {
                isStraight = false;
                break;
            }
        }
        if (isStraight && token.length == 5) return CardType.Straight;
        return CardType.Sigal;
    }

    private enum CardType {
        DoubleJoker, Bomb, Sigal, Double, Triple, Straight;
    }

    public static void main(String[] args) {
        Main main = new Main();
        Scanner in = new Scanner(System.in);
        while (in.hasNextLine()) {
            String s = in.nextLine();
            String[] token = s.split("-");
            System.out.println(main.play(token[0], token[1]));
        }
    }
}
```

# 11. ȥ<>Ķ<EFBFBD>-<2D><><EFBFBD>ֲ<EFBFBD><D6B2><EFBFBD>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ظ<EFBFBD>Ԫ<EFBFBD>ص<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>飬<EFBFBD><EFBFBD><EFBFBD>ֲ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫע<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD>㣺

- if (val <= A[m]) h = m;
- <20><>Ϊ h <20>ĸ<EFBFBD>ֵΪ m <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD> m - 1<><31><EFBFBD><EFBFBD><EFBFBD><EFBFBD> while ѭ<><D1AD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҳ<EFBFBD><D2B2>Ϊ l < h<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> m - 1 ѭ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ l <= h<EFBFBD><EFBFBD>

```java
public int getPos(int[] A, int n, int val) {
    int l = 0, h = n - 1;
    while (l < h) {
        int m = l + (h - l) / 2;
        if (val <= A[m]) h = m;
        else l = m + 1;
    }
    return A[h] == val ? h : -1;
}
```

# 12. ȥ<>Ķ<EFBFBD>-<2D>׸<EFBFBD><D7B8>ظ<EFBFBD><D8B8>ַ<EFBFBD>

```java
public char findFirstRepeat(String A, int n) {
    boolean[] hasAppear = new boolean[256];
    for (int i = 0; i < n; i++) {
        char c = A.charAt(i);
        if(hasAppear[c]) return c;
        hasAppear[c] = true;
    }
    return ' ';
}
```

# 13. ȥ<>Ķ<EFBFBD>-Ѱ<><D1B0>Coder

```java
public String[] findCoder(String[] A, int n) {
    List<Pair<String, Integer>> list = new ArrayList<>();
    for (String s : A) {
        int cnt = 0;
        String t = s.toLowerCase();
        int idx = -1;
        while (true) {
            idx = t.indexOf("coder", idx + 1);
            if (idx == -1) break;
            cnt++;
        }
        if (cnt != 0) {
            list.add(new Pair<>(s, cnt));
        }
    }
    Collections.sort(list, (o1, o2) -> (o2.getValue() - o1.getValue()));
    String[] ret = new String[list.size()];
    for (int i = 0; i < list.size(); i++) {
        ret[i] = list.get(i).getKey();
    }
    return ret;
}

// ţ<><C5A3><EFBFBD><EFBFBD><EFBFBD>޷<EFBFBD><DEB7><EFBFBD><EFBFBD><EFBFBD> javafx.util.Pair<69><72><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Լ<EFBFBD>ʵ<EFBFBD><CAB5>һ<EFBFBD><D2BB> Pair <20><>
private class Pair<T, K> {
    T t;
    K k;

    Pair(T t, K k) {
        this.t = t;
        this.k = k;
    }

    T getKey() {
        return t;
    }

    K getValue() {
        return k;
    }
}
```

# 14. <20><><EFBFBD><EFBFBD>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ

̰<EFBFBD>IJ<EFBFBD><EFBFBD>ԡ<EFBFBD>

```java
public int getDis(int[] A, int n) {
    int max = 0;
    int soFarMin = A[0];
    for (int i = 1; i < n; i++) {
        if(soFarMin > A[i]) soFarMin = A[i];
        else max = Math.max(max, A[i]- soFarMin);
    }
    return max;
}
```

# 15. <20><><EFBFBD><EFBFBD>-<2D><><EFBFBD>ӷ<EFBFBD>ת

```java
public int[][] flipChess(int[][] A, int[][] f) {
    int[][] direction = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};
    for (int[] ff : f) {
        for (int[] dd : direction) {
            int r = ff[0] + dd[0] - 1, c = ff[1] + dd[1] - 1;
            if(r < 0 || r > 3 || c < 0 || c > 3) continue;
            A[r][c] ^= 1;
        }
    }
    return A;
}
```

# 16. <20><><EFBFBD><EFBFBD>-<2D>ݷ<EFBFBD>

```java
private Set<String> paths;
private List<Integer> curPath;

public int countPath(int[][] map, int n, int m) {
    paths = new HashSet<>();
    curPath = new ArrayList<>();
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            if (map[i][j] == 1) {
                map[i][j] = -1;
                int[][] leftRightDirection = {{1, 0}, {-1, 0}};
                int[][] topDownDirection = {{0, 1}, {0, -1}};
                for (int[] lr : leftRightDirection) {
                    for (int[] td : topDownDirection) {
                        int[][] directions = {lr, td};
                        backtracking(map, n, m, i, j, directions);
                    }
                }
                return paths.size();
            }
        }
    }
    return 0;
}

private void backtracking(int[][] map, int n, int m, int r, int c, int[][] directions) {
    if (map[r][c] == 2) {
        String path = "";
        for (int num : curPath) {
            path += num;
        }
        paths.add(path);
        return;
    }
    for (int i = 0; i < directions.length; i++) {
        int nextR = r + directions[i][0];
        int nextC = c + directions[i][1];
        if (nextR < 0 || nextR >= n || nextC < 0 || nextC >= m || map[nextR][nextC] == -1) continue;
        map[nextR][nextC] = map[nextR][nextC] == 2 ? 2 : -1;
        curPath.add(nextR);
        curPath.add(nextC);
        backtracking(map, n, m, nextR, nextC, directions);
        curPath.remove(curPath.size() - 1);
        curPath.remove(curPath.size() - 1);
        map[nextR][nextC] = map[nextR][nextC] == 2 ? 2 : 0;
    }
}
```

# 17. <20><><EFBFBD><EFBFBD>-ֱ<><D6B1>ͼ<EFBFBD><CDBC><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

```java
public int countArea(int[] A, int n) {
    int max = 0;
    for (int i = 0; i < n; i++) {
        int min = A[i];
        for (int j = i; j < n; j++) {
            min = Math.min(min, A[j]);
            max = Math.max(max, min * (j - i + 1));
        }
    }
    return max;
}
```

# 18. <20><><EFBFBD><EFBFBD>-<2D>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

<EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Сд<EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>԰<EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 26 <20><><EFBFBD>ơ<EFBFBD><C6A1><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֵ<EFBFBD><D6B5><EFBFBD><EFBFBD>ıȽϺ<C8BD><CFBA><EFBFBD>ͨ<EFBFBD><CDA8><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ƚϲ<C8BD>ͬ<EFBFBD><CDAC><EFBFBD>Ǵ<EFBFBD><C7B4><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ҽ<EFBFBD><D2BD>бȽϣ<C8BD><CFA3><EFBFBD><EFBFBD><EFBFBD> "ac" <20><> "abc"<22><><EFBFBD>ֵ<EFBFBD><D6B5><EFBFBD><EFBFBD>ıȽϽ<C8BD><CFBD><EFBFBD>Ϊ "ac" > "abc"<22><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ƚϣ<C8BD><CFA3><EFBFBD>Ϊ "abc" <20><><EFBFBD><EFBFBD>λ<EFBFBD><CEBB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ȼ<EFBFBD><C8BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ij<EFBFBD><EFBFBD>ȿ<EFBFBD><EFBFBD>ܲ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ȣ<EFBFBD><EFBFBD><EFBFBD> s1 <20>հײ<D5B0><D7B2>ֺ<EFBFBD> s2 <20><>Ӧ<EFBFBD><D3A6><EFBFBD>ֽ<EFBFBD><D6BD>бȽ<D0B1>ʱ<EFBFBD><CAB1>Ӧ<EFBFBD>ð<EFBFBD> s1 <20>Ŀհײ<D5B0><D7B2>ֿ<EFBFBD><D6BF><EFBFBD><EFBFBD><EFBFBD> 'a' <20>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ġ<EFBFBD>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD>һ<EFBFBD><EFBFBD>Ҫע<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ǣ<EFBFBD>s1 <20><> s2 <20><><EFBFBD><EFBFBD>Ϊ len<sub>i</sub> <20><><EFBFBD>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֻ<EFBFBD>Ƚ<EFBFBD>ǰ<EFBFBD><C7B0> i <20><><EFBFBD>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 'aaa' <20><> 'bbb' <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϊ 2 <20>ĸ<EFBFBD><C4B8><EFBFBD>Ϊ 'aa' <20><> 'bb' <20><><EFBFBD>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><D2AA><EFBFBD>Ǻ<EFBFBD><C7BA>沿<EFBFBD>ֵ<EFBFBD><D6B5>ַ<EFBFBD><D6B7><EFBFBD>

<EFBFBD><EFBFBD>ͳ<EFBFBD>Ƹ<EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD> len1 <20><>ʼһֱ<D2BB><D6B1><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ϸ<EFBFBD><CFB7><EFBFBD><EFBFBD>ȣ<EFBFBD>ÿ<EFBFBD><C3BF>ѭ<EFBFBD><D1AD><EFBFBD><EFBFBD>ͳ<EFBFBD>Ƴ<EFBFBD><C6B3><EFBFBD>Ϊ i <20><><EFBFBD><EFBFBD><EFBFBD>ַ<EFBFBD><D6B7><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

```java
String s1 = in.next();
String s2 = in.next();
int len1 = in.nextInt();
int len2 = in.nextInt();
int len = Math.min(s2.length(), len2);
int[] subtractArr = new int[len];
for (int i = 0; i < len; i++) {
    char c1 = i < s1.length() ? s1.charAt(i) : 'a';
    char c2 = s2.charAt(i);
    subtractArr[i] = c2 - c1;
}
int ret = 0;
for (int i = len1; i <= len; i++) {
    for (int j = 0; j < i; j++) {
        ret += subtractArr[j] * Math.pow(26, i - j - 1);
    }
}
System.out.println(ret - 1);
```

# 19. <20><><EFBFBD><EFBFBD>-ƽ<><C6BD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

```java
int W = in.nextInt();
double Y = in.nextDouble();
double x = in.nextDouble();
int N = in.nextInt();
while (N-- > 0) {
    Y++; // <20><>Ա<EFBFBD><D4B1>ÿ<EFBFBD><C3BF><EFBFBD><EFBFBD><EFBFBD>䶼Ҫ<E4B6BC><D2AA> 1
    Y += (21 - Y) * x;
}
System.out.println((int) Math.ceil(Y));
```

# 20. <20>ٶ<EFBFBD>-<2D>ﷸת<EFB7B8><D7AA>

<EFBFBD><EFBFBD><EFBFBD>ֺ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>⣬<EFBFBD><EFBFBD>ÿ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>IJ<EFBFBD><EFBFBD>ֺͻ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

```java
int n = in.nextInt();
int t = in.nextInt();
int c = in.nextInt();
int[] values = new int[n];
for (int i = 0; i < n; i++) {
    values[i] = in.nextInt();
}
int cnt = 0;
int totalValue = 0;
for (int s = 0, e = c - 1; e < n; s++, e++) {
    if (s == 0) {
        for (int j = 0; j < c; j++) totalValue += values[j];
    } else {
        totalValue = totalValue - values[s - 1] + values[e];
    }
    if (totalValue <= t) cnt++;
}
System.out.println(cnt);
```

# 22. <20>ٶ<EFBFBD>-<2D>ü<EFBFBD><C3BC><EFBFBD><EFBFBD><EFBFBD>ֽ

```java
int n = in.nextInt();
int minX, minY, maxX, maxY;
minX = minY = Integer.MAX_VALUE;
maxX = maxY = Integer.MIN_VALUE;
for (int i = 0; i < n; i++) {
    int x = in.nextInt();
    int y = in.nextInt();
    minX = Math.min(minX, x);
    minY = Math.min(minY, y);
    maxX = Math.max(maxX, x);
    maxY = Math.max(maxY, y);
}
System.out.println((int) Math.pow(Math.max(maxX - minX, maxY - minY), 2));
```

# 23. <20>ٶ<EFBFBD>-<2D><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

P ( <20><><EFBFBD>ٵ<EFBFBD>һ<EFBFBD><D2BB><EFBFBD><EFBFBD> ) = 1 - P ( һ<><D2BB>Ҳ<EFBFBD><D2B2><EFBFBD><EFBFBD><EFBFBD><EFBFBD> )

<EFBFBD>ӣ<EFBFBD><EFBFBD><EFBFBD>ȡ<EFBFBD><EFBFBD><EFBFBD>ʾ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫһ<EFBFBD><EFBFBD>һ<EFBFBD>н<EFBFBD><EFBFBD>ж<EFBFBD>ȡ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ֱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD> in.nextDouble()<29><>

```java
public static void main(String[] args) {
    Scanner in = new Scanner(System.in);
    while (in.hasNext()) {
        int n = in.nextInt();
        int m = in.nextInt();
        int x = in.nextInt();
        int y = in.nextInt();
        int t = in.nextInt();
        in.nextLine(); // <20><>
        double pcc = 0.0;
        double sum = 0.0;
        for (int i = 1; i <= n; i++) {
            String[] token = in.nextLine().split(" "); // <20><>
            for (int j = 1; j <= m; j++) {
                double p = Double.parseDouble(token[j - 1]);
                //  double p = in.nextDouble();
                sum += p;
                if (i == x && j == y) {
                    pcc = p;
                }
            }
        }
        double pss = sum / (n * m);
        pcc = computePOfIRT(pcc, t);
        pss = computePOfIRT(pss, t);
        System.out.println(pcc > pss ? "cc" : pss > pcc ? "ss" : "equal");
        System.out.printf("%.2f\n", Math.max(pcc, pss));
    }
}

// compute probability of independent repeated trials
private static double computePOfIRT(double p, int t) {
    return 1 - Math.pow((1 - p), t);
}
```

# 24. <20>ٶ<EFBFBD>-Ģ<><C4A2><EFBFBD><EFBFBD>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>û<EFBFBD><EFBFBD>ݻᳬʱ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Ҫ<EFBFBD><EFBFBD> DP<44><50>

dp[i][j] <20><>ʾ<EFBFBD><CABE><EFBFBD><EFBFBD> (i,j) λ<>ò<EFBFBD><C3B2>ᴥ<EFBFBD><E1B4A5>Ģ<EFBFBD><C4A2><EFBFBD>ĸ<EFBFBD><C4B8>ʡ<EFBFBD><CAA1><EFBFBD><EFBFBD><EFBFBD> N\*M <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> i == N || j == M<><4D><EFBFBD><EFBFBD>ô (i,j) ֻ<><D6BB><EFBFBD><EFBFBD>һ<EFBFBD><D2BB><EFBFBD>ƶ<EFBFBD><C6B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƶ<EFBFBD><C6B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>¾<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>е<EFBFBD> 3 <20>к͵<D0BA> 3 <20><>ֻ<EFBFBD><D6BB><EFBFBD><EFBFBD>һ<EFBFBD><D2BB><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƶ<EFBFBD><C6B6><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>λ<EFBFBD>ÿ<EFBFBD><C3BF><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ƶ<EFBFBD><C6B6><EFBFBD>


```java
int N = in.nextInt();
int M = in.nextInt();
int K = in.nextInt();
boolean[][] mushroom = new boolean[N][M];
while (K-- > 0) {
    int x = in.nextInt();
    int y = in.nextInt();
    mushroom[x - 1][y - 1] = true;
}
double[][] dp = new double[N][M];
dp[0][0] = 1;
for (int i = 0; i < N; i++) {
    for (int j = 0; j < M; j++) {
        if (mushroom[i][j]) dp[i][j] = 0;
        else {
            double cur = dp[i][j];
            if (i == N - 1 && j == M - 1) break;
            if (i == N - 1) dp[i][j + 1] += cur;
            else if (j == M - 1) dp[i + 1][j] += cur;
            else {
                dp[i][j + 1] += cur / 2;
                dp[i + 1][j] += cur / 2;
            }
        }
    }
}
System.out.printf("%.2f\n", dp[N - 1][M - 1]);
```