Intersection of Two Arrays LeetCode solution in C++

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class Solution {
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 public:
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  // what i think is we have to return the intersection elements from both nums
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  vector<int> intersection(vector<int> &nums1, vector<int> &nums2) {
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    // result vector which will store those values which will be intersecting in
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    // both nums
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    vector<int> result;
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    // map intersection, which will store values of all the elements in num1
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    unordered_map<int, int> intersection;
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    // map will store all the values of num1(as key),with corresponding value 1
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    for (auto character : nums1) {
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      intersection[character] = 1;
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    }
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    // this loop will check if any element of num1 is there in num2? if yes,
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    // insert it in result after inserting it once, make its corresponding value
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    // to 0 so that if you find any elements, that is repeating in num2, as well
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    // as present in num1 so you dont enter it twice in result, you should enter
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    // it once only
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    for (auto character : nums2) {
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      // if found once, it's value would be 1, so entered in result
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      // after it is entered in result, its value we change to 0
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      // so agin if that same element repeats, due to 0 as its value, we avoid
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      // pushing it to result
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      if (intersection[character]) {
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        result.push_back(character);
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        intersection[character] = 0;
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      }
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    }
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    // after getting all the intersecting elements,we return result
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    return result;
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  }
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};