Submission #3571544

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Source Code Expand

#include <iostream>
#include <cstdio>
#include <cmath>
using namespace std;

int main()
{
  double r, n, m;
  cin >> r >> n >> m;

  double ans = 0;
  for(int i = 1; i < n + m; i++){
    double a = r * sqrt(1 - (1-i*2/n)*(1-i*2/n));
    if(i > m){
      double b = r * sqrt(1 - (1-(i-m)*2/n)*(1-(i-m)*2/n));
      if(i < n) ans += max(a, b);
      else ans += b;
    } else {
      ans += a;
    }
  }

  printf("%.7f\n", ans*2);

  return 0;
}

Submission Info

Judge Result