func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     long long t, i, j, k, l, r;     cin >> t;     while (t--) {       cin >> l >> r;       if (l == r) {         if (l % 2 == 0)           cout << l << endl;         else           cout <<  -  << l << endl;       } else if (l % 2 == 1 && r % 2 == 1) {         cout <<  -  << (l + r) / 2 << endl;       } else if (l % 2 == 0 && r % 2 == 0) {         cout << (l + r) / 2 << endl;       } else if (l % 2 == 0 && r % 2 == 1) {         cout <<  -  << (r - l + 1) / 2 << endl;       } else         cout << (r - l + 1) / 2 << endl;     }   }   