找出一个列表里面的所有的两数之和

class Solution {
public:
    vector twoSum(vector& nums, int target) {
        int idx = 0;
        auto v = nums;
        vector plusInfo = {};
        for (std::vector::iterator i = v.begin(); i != v.end(); ++i)
        {
            int value = *i;
            int idx2 = idx;
            for (std::vector::iterator p = i+1; p != v.end(); ++p)
            {
                idx2 = idx2 + 1;

                int value2 = *p;
                int plusValue = value + value2;
                if (plusValue == target)
                {
                    plusInfo.push_back(idx);
                    plusInfo.push_back(idx2);
                }
            }

            idx = idx + 1;
        }

        return plusInfo;
    }
};

上面的是可以的，没有问题的，但其实刚开始的时候我并不是这样写的，这是改过之后的，刚开始写的在leetcode上运行一直报内存错误的错误，我找了一下原因是因为，最后的
v.end() 指向的是列表里面最后一个元素的下一个，我用while遍历的时候访问了这个，所以报错，可以看一下原来的代码

class Solution {
public:
    vector twoSum(vector& nums, int target) {
        int idx = 0;
        auto v = nums;
        vector plusInfo = {};
        for (std::vector::iterator i = v.begin(); i != v.end(); ++i)
        {
            int value = *i;
            int idx2 = idx;
            std::vector::iterator p = i;
            //----------------------------------
            while(p != v.end())
            {
                p = p + 1;
                idx2 = idx2 + 1;

                int value2 = *p;
                int plusValue = value + value2;
                if (plusValue == target)
                {
                    plusInfo.push_back(idx);
                    plusInfo.push_back(idx2);
                }
            }
            //----------------------------------

            idx = idx + 1;
        }

        return plusInfo;
    }
};