Codeforces Round #421 B. Mister B and Angle in Polygon

题意分析:

代码:

#include <iostream>
#include <algorithm>

using namespace std;

int main(int argc, char const *argv[])
{
int n, a;
while (~scanf("%d %d", &n, &a))
{
int ans = 3;
double deg = 180.0 * (n - 2) / n; // 最大角度数
double ang = (180 - deg) / 2; // 最小角度数
double tmp;
for (int i = 4; i <= n; i++)
{
tmp = (180.0 - deg) * (i - 2) / 2; // 公式推导可得
if (abs(ang - a) > abs(tmp - a))
{
ang = tmp;
ans = i;
}
}
printf("2 1 %d\n", ans);
}
return 0;
}