6-29刷题

    int removeElement(vector<int> &A, int elem) {
        int i = 0;
        int pointer = A.size() - 1;
        while (i <= pointer) {
            if (A[i] == elem) {
                A[i] = A[pointer];
                --pointer;
            } else {
                ++i;
            }
        }
        return pointer + 1;
    }

    public ArrayList<Integer> subarraySum(int[] nums) {
        ArrayList<Integer> ret = new ArrayList<Integer>();
        for (int i = 0; i < nums.length; ++i) {
            int sum = 0;
            for (int j = i; j < nums.length; ++j) {
                sum += nums[j];
                if (sum == 0) {
                    ret.add(i);
                    ret.add(j);
                    return ret;
                }
            }
        }
        return ret;
    }