题解 | #和为S的连续正数序列#

import java.util.ArrayList;
public class Solution {
    public ArrayList<ArrayList<Integer> > FindContinuousSequence(int sum) {
        ArrayList<ArrayList<Integer> > ret = new ArrayList<ArrayList<Integer> >();
        int start = 1;
        int end = 2;
        int Cursum = start + end;
        while(end <= sum / 2 + 1) {
            if(Cursum == sum){
                ArrayList<Integer> list = new ArrayList<Integer>();
                for(int i = start;i<=end;i++){
                    list.add(i);
                }
                ret.add(list);
                end++;
                Cursum += end;
            } else if(Cursum < sum){
                end++;
                Cursum += end;
            } else{
                Cursum -= start;
                start++;
            }
        }
        return ret;
    }
}