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two-sum.cpp
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two-sum.cpp
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// Given an array of integers, return indices of the two numbers such that they add up to a specific target.
//
// You may assume that each input would have exactly one solution, and you may not use the same element twice.
//
// Example:
//
//
// Given nums = [2, 7, 11, 15], target = 9,
//
// Because nums[0] + nums[1] = 2 + 7 = 9,
// return [0, 1].
//
//
//
//
class Solution {
public:
vector<int> twoSum(vector<int>& nums, int target) {
unordered_map<int, int> hashMap;
for (int i = 0; i < nums.size(); i++) {
if (hashMap.find(target - nums[i]) == hashMap.end()) {
// hashMap[nums[i]] = i;
hashMap.insert(make_pair(nums[i], i));
}
else {
return {hashMap[target - nums[i]],i};
}
}
return {};
}
};