CS-Notes/notes/57.2 和为 S 的连续正数序列.md

# 57.2 和为 S 的连续正数序列

## 题目描述

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## 题目描述

输出所有和为 S 的连续正数序列。例如和为 100 的连续序列有：

```
[9, 10, 11, 12, 13, 14, 15, 16]
[18, 19, 20, 21, 22]。
```

## 解题思路

```java
public ArrayList<ArrayList<Integer>> FindContinuousSequence(int sum) {
    ArrayList<ArrayList<Integer>> ret = new ArrayList<>();
    int start = 1, end = 2;
    int curSum = 3;
    while (end < sum) {
        if (curSum > sum) {
            curSum -= start;
            start++;
        } else if (curSum < sum) {
            end++;
            curSum += end;
        } else {
            ArrayList<Integer> list = new ArrayList<>();
            for (int i = start; i <= end; i++)
                list.add(i);
            ret.add(list);
            curSum -= start;
            start++;
            end++;
            curSum += end;
        }
    }
    return ret;
}
```






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