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class Solution {
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 public:
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  vector<int> sumEvenAfterQueries(vector<int> &nums, vector<vector<int>> &queries) {
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    // Sum of all even numbers in the array intially
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    int tes = accumulate(nums.begin(), nums.end(), 0, [](int curr, int a) {
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      if (a % 2 == 0)
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        return curr += a;
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      else
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        return curr;
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    });
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    vector<int> ans(queries.size());
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    bool a = false, b = false;
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    for (int i = 0; i < queries.size(); i++) {
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      // If both are even or odd it stays even then
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      a = nums[queries[i][1]] % 2 == 0 && queries[i][0] % 2 == 0;
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      b = abs(nums[queries[i][1]] % 2) == 1 && abs(queries[i][0] % 2) == 1;
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      if (a)
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        tes += queries[i][0];
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      else if (b)
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        tes += queries[i][0] + nums[queries[i][1]];
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      else if (nums[queries[i][1]] % 2 == 0)
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        tes -= nums[queries[i][1]];         // If even turns to odd because of operation
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                                            // remove that even value from ans
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      ans[i] = tes;                         // Adding the result
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      nums[queries[i][1]] += queries[i][0]; // now completing the operation in queries to use in
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                                            // further operations
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    }
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    return ans;
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  }
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};