Given an array of integers that is already sorted in ascending order, find two numbers such that they add up to a specific target number.
The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2. Please note that your returned answers (both index1 and index2) are not zero-based.
You may assume that each input would have exactly one solution and you may not use the same element twice.
Input: numbers={2, 7, 11, 15}, target=9 Output: index1=1, index2=2
s思路： 1. 排好序的情況，說明不考慮map，但可以用two pointer：左邊一個、右邊一個，往中間走！ 2. two pointer對排好序的情況，很好用！
class Solution {public: vector<int> twoSum(vector<int>& numbers, int target) { // int l=0,r=numbers.size()-1; while(l<r){ if(numbers[l]+numbers[r]==target) break; if(numbers[l]+numbers[r]<target){ l++; }else r--; } //return {l++,r++};//bug:應(yīng)該先++ return {++l,++r}; }};新聞熱點
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