Submission #7077570

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
#define mod 1000000007
 
int gcd(int a, int b) { return b ? gcd(b, a%b) : a; }
 
int lcm(int a, int b) { return a * b / gcd(a, b); }

double calc(int r, int n, int x){
    if(x <= 0 || x >= n){
        return 0;
    }
    double k = fabs(r - (2 * r) / n * x); // 中心からの距離
    return sqrt(r * r - k * k) * 2;
}

int main(){
    int n, m;
    double r;
    cin >> r >> n >> m;
    double ans = 0;
    for (int i = 0; i <= n + m; i++){
        ans += max(calc(r, n, i), calc(r, n, i - m));
    }
    printf("%.10f\n", ans);
    return 0;
}

Submission Info

Judge Result