func_code_string: #include <bits/stdc++.h>   using namespace std;   const double pp = 0.00000001;   const int maxn = 100005;   double ans, xo, da, mid;   int ci, w, i, n, x[maxn], y[maxn];   bool pd(double k) {     double ww, l = -1e9, r = 1e9;     int i;     for (i = 1; i <= n; i++) {       if (k * k < (y[i] - k) * (y[i] - k)) {         return 0;       }       ww = -1.0 * y[i] * y[i] + 2 * y[i] * k;       ww = sqrt(ww);       if (l < x[i] - ww) l = x[i] - ww;       if (r > x[i] + ww) r = x[i] + ww;     }     if (l <= r)       return true;     else       return false;   }   int main() {     scanf( %d , &n);     for (i = 1; i <= n; i++) {       scanf( %d%d , &x[i], &y[i]);       if (y[i] > 0)         w++;       else         y[i] = -y[i];     }     if (w != 0 && w != n) {       printf( -1 n );       return 0;     }     xo = 0;     da = 50000000000000.4949989;     ci = 0;     while (ci <= 100) {       ci++;       mid = (xo + da) / 2;       if (pd(mid)) {         ans = mid;         da = mid;       } else         xo = mid;     }     printf( %lf n , mid);     return 0;   }   