Create 3790_cnblogs.cpp

From http://www.cnblogs.com/qiufeihai/archive/2012/03/15/2398455.html

HDOJ/3790_cnblogs.cpp

@@ -0,0 +1,144 @@
+#include <set>
+#include <map>
+#include <list>
+#include <cmath>
+#include <ctime>
+#include <deque>
+#include <queue>
+#include <stack>
+#include <cstdio>
+#include <string>
+#include <vector>
+#include <cctype>
+#include <cstring>
+#include <sstream>
+#include <fstream>
+#include <cstdlib>
+#include <cassert>
+#include <iostream>
+#include <algorithm>
+ 
+using namespace std;
+//Constant Declaration
+/*--------------------------*/
+//#define LL long long 
+#define LL __int64
+const int M=1100;//最多点数
+const int INF=1<<30;
+const double EPS = 1e-11;
+const double PI = acos(-1.0);
+/*--------------------------*/
+// some essential funtion
+/*----------------------------------*/
+void Swap(int &a,int &b){   int t=a;a=b;b=t; }
+int Max(int a,int b){   return a>b?a:b;  }
+int Min(int a,int b){   return a<b?a:b;  }
+int Gcd(int a,int b){   while(b){b ^= a ^=b ^= a %= b;}  return a; }
+/*----------------------------------*/
+//for (i = 0; i < n; i++)
+/*----------------------------------*/
+
+struct djs
+{
+    int l,p;
+}d[M],g[M][M];
+
+bool used[M];//标记i是否被用过
+void init(int n)
+{
+    int i, j;
+    for (i = 1; i <= n; i++)
+    {
+        for (j = 1; j <= n; j++)
+        {
+            g[i][j].l = INF;//初始化图没有边，默认为INF,为了一定更新
+            g[i][j].p = INF;
+        }
+    }
+    for (i = 1; i <= n; i++)
+    {
+        d[i].l = INF;
+        d[i].p = INF;
+    }
+    
+    memset(used, 0, sizeof(used));
+}
+
+
+
+int dijkstra(int star, int end, int n)//起点，终点，总点数(编号为1,2...n)
+{
+    int min_num;//最小值的位置
+    int i;
+    d[star].l= 0;
+    d[star].p= 0;//起点到起点的最短距离为0，很重要的一步
+    for (int cnt = 0; cnt < n; cnt++)//注意别用while(n--),这样会改变n的值。n次贪心
+    {
+        int min = INF;
+        for (i = 1; i <= n; i++)
+        {
+            if (!used[i] && d[i].l < min)
+            {
+                min = d[i].l;
+                min_num = i;
+            }
+        }
+        
+        used[min_num] = 1;
+
+        //把d[min_num]作为中间点，对相邻的点做松弛
+        for (i = 1; i <= n; i++)
+        {
+            if (!used[i] && d[i].l > d[min_num].l + g[min_num][i].l)
+            {
+                d[i].l = d[min_num].l + g[min_num][i].l;
+                d[i].p = d[min_num].p + g[min_num][i].p;
+            }
+            if (!used[i] && d[i].l == d[min_num].l + g[min_num][i].l && d[i].p > d[min_num].p + g[min_num][i].p)//这里的判断是关键
+            {
+                d[i].p = d[min_num].p + g[min_num][i].p;
+            }
+        }
+        
+    }
+    return d[end].l;
+}
+
+
+
+
+
+int main()
+{
+ //freopen("in.txt","r",stdin);
+ //freopen("out.txt","w",stdout);
+ //int t, case1 = 0;
+ //scanf("%d", &t);
+ int n, m;
+ int i, j;
+ while (scanf("%d%d", &n, &m), n + m)
+ {
+     init(n);
+    for (i = 0; i < m; i++)
+    {
+        int a, b, c, c1;
+        scanf("%d%d%d%d", &a, &b, &c, &c1);
+        if (g[a][b].l > c)
+        {
+            g[b][a].l = g[a][b].l = c;
+            g[b][a].p= g[a][b].p = c1;
+        }//此题为无向图
+        if (g[a][b].l == c && g[b][a].p > c1)//这里的判断是关键
+        {
+            g[b][a].p= g[a][b].p = c1;
+        }
+
+    }
+    int star, end,ans;
+    scanf("%d%d", &star, &end);
+    ans = dijkstra(star, end, n);
+    printf("%d %d\n", ans, d[end].p);
+ }
+ 
+ return 0;
+}