hdu 4798 Skycity（几何）

题目链接：hdu 4798 Skycity

代码

#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>

using namespace std;
const double pi = 4 * atan(1.0);

int F;
double R, L, H, S;

double solve (double r, double h) {
    int n = pi / atan(S/2/h/r);
    double rad = pi / n;
    return 2 * r * n * tan(pi / n);
}

int main () {
    while (scanf("%lf%lf%lf%d%lf", &R, &L, &H, &F, &S) == 5) {
        double ans = 0, r = (R - L) / F, h = H / F;
        for (int i = 0; i < F; i++)
            ans += solve(L + r * i, h) * h;
        printf("%.3lf\n", ans);
    }
    return 0;
}