题解 | #两数之和#

class Solution {
public:
    /**
     * 
     * @param numbers int整型vector 
     * @param target int整型 
     * @return int整型vector
     */
    vector<int> twoSum(vector<int>& numbers, int target) {
        // write code here
        vector<int> copy = numbers;
        sort(numbers.begin(),numbers.end());

        for(int i=0;i<numbers.size();i++){
            int index = binaryfind(numbers, target - numbers[i]);
//             cout<<index<<" "<<i<<" ";
            if(index!=-1 && index!=i) {
//                 cout<<"jin";
//                 return {i,index};
                vector<int> res;
                for(int j=0;j<numbers.size();j++) {
//                     for(auto a : res) {
//                         cout<<a<<" ";
//                     }

                    if(copy[j] == numbers[index] || copy[j] ==numbers[i]) {
                        res.emplace_back(j+1);
                    }
                    if(res.size()==2) {
                        return res;
                    }
                }
            }
        }
        return {};

    }

    int binaryfind(vector<int>& numbers , int target) {
        // 左闭右开
        int left =0;
        int right = numbers.size();
        // 那么结束的条件就是 left=right

        while(left<right) {
            int mid = left + (right-left)/2;
            int value = numbers[mid];
            if(target==value){
                return mid;
            } else if(target>value) {
                left = mid+1;
            } else if(target<value) {
                right=mid;
            }
        }

        return -1;
    }
};