Maximum Matrix Sum LeetCode solution in C++

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/**
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 * @author      : archit
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 * @GitHub      : archit-1997
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 * @Email       : architsingh456@gmail.com
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 * @file        : maximumMatrixSum.cpp
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 * @created     : Saturday Aug 21, 2021 20:11:56 IST
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 */
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#include <bits/stdc++.h>
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using namespace std;
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class Solution {
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 public:
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  long long maxMatrixSum(vector<vector<int>> &matrix) {
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    int r = matrix.size(), c = matrix[0].size();
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    // we need to find the min number in the matrix and also count of negative
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    // numbers in the matrix
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    int small = INT_MAX, count = 0;
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    long long int sum = 0;
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    for (int i = 0; i < r; i++) {
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      for (int j = 0; j < c; j++) {
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        int val = matrix[i][j];
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        // finding the smallest absolute value in the matrix
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        small = min(small, abs(val));
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        // counting the negative numbers
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        if (val < 0) count++;
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        // finding the sum of all the values
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        sum += abs(val);
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      }
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    }
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    // if even number of negatives, then just return sum
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    if (count % 2 == 0)
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      return sum;
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    else
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      // subtract the value of the min absolute element
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      return sum - 2 * small;
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  }
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};