func_code_string: #include <bits/stdc++.h>   using namespace std;   const int dx[9] = {0, 1, -1, 0, 0, -1, -1, 1, 1};   const int dy[9] = {0, 0, 0, -1, 1, -1, 1, -1, 1};   const double pi = acos(-1.0);   const int N = 110;   long long n, m, ans;   void input_data() { cin >> n >> m; }   void get_ans() {     if (n <= m) {       ans = n;       return;     }     n -= (m + 1);     if (n <= 0) {       ans = m + 1;       return;     }     long long l = 0, r = 2e9 + 2, t = 0;     ans = m;     while (l <= r) {       long long mid = (l + r) >> 1;       long long temp = (mid + 2) * (mid - 1) / 2;       if (temp >= n) {         t = mid;         r = mid - 1;       } else         l = mid + 1;     }     ans += t;   }   void o() { cout << ans << endl; }   int main() {     input_data();     get_ans();     o();     return 0;   }   