func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, cnt, flag = 0;     cin >> n;     int a, b, c = 0;     for (int i = 1; i <= n; i++) {       cin >> a >> b;       if (b - a >= 2) ++c;     }     cout << c << endl;   }   