func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, m;     scanf( %d%d , &n, &m);     int l = (n - 1) / m;     if ((n - 1) % m == 0)       printf( %d n , 2 * l);     else       printf( %d n , 2 * l + 1 + ((n - 1) % m >= 2));     int need = (n - 1) % m;     for (int i = 2; i <= n;) {       int maxn = min(n, i + l - 1 + (need-- > 0));       printf( %d %d n , 1, i);       int j = i;       while (j++ < maxn) printf( %d %d n , j - 1, j);       i = maxn + 1;     }     return 0;   }   