func_code_string: #include <bits/stdc++.h>   using namespace std;   inline int read() {     int f = 1, x = 0;     char ch;     do {       ch = getchar();       if (ch ==  - ) f = -1;     } while (ch <  0  || ch >  9 );     do {       x = (x << 3) + (x << 1) + ch -  0 ;       ch = getchar();     } while (ch >=  0  && ch <=  9 );     return f * x;   }   int r, x, y, px, py;   int main() {     scanf( %d%d%d%d%d , &r, &x, &y, &px, &py);     double dis = sqrt(1.0 * (x - px) * (x - px) + 1.0 * (y - py) * (y - py));     printf( %d n , (int)(ceil(1.0 * dis / (2.0 * r))));   }   