func_code_string: #include <bits/stdc++.h>   using namespace std;   int32_t main() {     ios_base::sync_with_stdio(false);     long long n, m, k;     cin >> n >> m >> k;     long long l = 1, r = 1e9 + 1;     while (r - l > 1) {       long long mid = (l + r) / 2;       long long ans = mid;       if (k >= mid) ans += ((mid - 1) * mid) / 2;       if (k > mid) ans += k - mid;       if (k < mid)         ans += (((mid - 1) + (k - mid)) * ((mid - 1) - (k - mid) + 1)) / 2;       long long t = n - k + 1;       if (t >= mid) ans += ((mid - 1) * mid) / 2;       if (t > mid) ans += t - mid;       if (t < mid)         ans += (((mid - 1) + (t - mid)) * ((mid - 1) - (t - mid) + 1)) / 2;       if (ans > m)         r = mid;       else         l = mid;     }     cout << l << endl;   }   