Preface
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Problem Statement
Given an array of integers nums and an integer target value target, find the two integers in the array whose sum equals the target value target, and return their array indices.
You may assume that each input would have exactly one solution. However, the same element in the array may not appear twice in the answer.
You may return the answer in any order.
Example 1
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输入：nums = [2,7,11,15], target = 9
输出：[0,1]
解释：因为 nums[0] + nums[1] == 9 ，返回 [0, 1] 。
Example 2
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输入：nums = [3,2,4], target = 6
输出：[1,2]
Example 3
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输入：nums = [3,3], target = 6
输出：[0,1]
Answer
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class Solution {
public:
vector<int> twoSum(vector<int>& nums, int target) {
int n = nums.size();
for (int i = 0; i < n; ++i) {
for (int j = i+1; j < n; ++j) {
if (nums[i] + nums[j] == target) {
return {i,j};
}
}
}
return {};
}
};