func_code_string: #include <bits/stdc++.h>   using namespace std;   long long int mod = 1000000007;   long long int numOfPoints(long long int &x, long long int &y, long long int &n,                             long long int t) {     long long int region1 = 2 * t * (t + 1) + 1;     long long int region2;     if (y - t >= 1)       region2 = 0;     else       region2 = abs(y - t - 1) * abs(y - t - 1);     long long int region3;     if (y + t <= n)       region3 = 0;     else       region3 = abs(n - y - t) * abs(n - y - t);     long long int region4;     if (x - t >= 1)       region4 = 0;     else       region4 = abs(x - t - 1) * abs(x - t - 1);     long long int region5;     if (x + t <= n)       region5 = 0;     else       region5 = abs(n - x - t) * abs(n - x - t);     long long int region6;     if (t >= (n + 1 - y) + (n + 1 - x))       region6 = (t - (n + 1 - y) - (n + 1 - x) + 1) *                 (t - (n + 1 - y) - (n + 1 - x) + 2) / 2;     else       region6 = 0;     long long int region7;     if (t >= (n + 1 - y) + (x - 0))       region7 =           (t - (n + 1 - y) - (x - 0) + 1) * (t - (n + 1 - y) - (x - 0) + 2) / 2;     else       region7 = 0;     long long int region8;     if (t >= (y - 0) + (n + 1 - x))       region8 =           (t - (y - 0) - (n + 1 - x) + 1) * (t - (y - 0) - (n + 1 - x) + 2) / 2;     else       region8 = 0;     long long int region9;     if (t >= (y - 0) + (x - 0))       region9 = (t - (y - 0) - (x - 0) + 1) * (t - (y - 0) - (x - 0) + 2) / 2;     else       region9 = 0;     return region1 - region2 - region3 - region4 - region5 + region6 + region7 +            region8 + region9;   }   int main() {     long long int i, j, k, l, m, n, p, q, x, y, z, a, b, c, r, fs, ls, md;     scanf( %lld , &n);     scanf( %lld , &x);     scanf( %lld , &y);     scanf( %lld , &c);     if (c == 1) {       printf( 0 n );       return 0;     }     fs = 0, ls = 2000000007LL;     while (fs + 1 < ls) {       md = (fs + ls) / 2;       if (c <= numOfPoints(x, y, n, md))         ls = md;       else         fs = md;     }     printf( %lld n , ls);     return 0;   }   