func_code_string: #include <bits/stdc++.h>   using namespace std;   long n, m, l, r, T, mid;   bool check(long long x) {     long long p = x * m, s = 1, d = n, t;     for (long i = 0; i <= x && p >= 0 && d; i++) {       d -= (t = min(s, d));       p -= t * i;       s = s * (x - i) / (i + 1);     }     return p >= 0 && !d;   }   int main() {     for (scanf( %ld , &T); T; T--) {       scanf( %ld%ld , &n, &m);       m = min(m, n / 2);       l = 0;       r = n;       while (l < r) {         mid = (l + r) / 2;         if (check(mid))           r = mid;         else           l = mid + 1;       }       printf( %ld n , r);     }     return 0;   }   