func_code_string: #include <bits/stdc++.h>   #pragma GCC diagnostic ignored  -Wunused-result    #pragma GCC diagnostic ignored  -Wsign-compare    using namespace std;   void solve();   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     int test_case = 1;     cin >> test_case;     while (test_case--) {       solve();     }     cerr <<  time taken :   << (float)clock() / CLOCKS_PER_SEC <<   secs  << endl;     return 0;   }   void solve() {     int n, m, t;     vector<int> arr;     bool odd = false;     bool zero = false;     cin >> n >> m;     for (int i = 0; i < n; i++) {       for (int j = 0; j < m; j++) {         cin >> t;         if (t == 0) {           zero = true;         }         if (t < 0) {           odd = !odd;           arr.push_back(-t);         } else {           arr.push_back(t);         }       }     }     sort(arr.begin(), arr.end());     int sum = 0;     for (int i = 0; i < arr.size(); i++) {       sum += arr[i];     }     if (zero) {       cout << sum << endl;     } else {       if (odd) {         sum -= 2 * arr[0];         cout << sum << endl;       } else {         cout << sum << endl;       }     }   }   