# include <iostream>
# include <cstdio>
using namespace std;
int main()
{
    int n;
    double sum = 0;
    scanf("%d", &n);
    if(n <= 150)
    {
        for (int i = 1; i <= n; i++)
        {
            sum += 0.4463;
        }
    }
    else if(n > 150 && n <= 400)
    {
        for (int i = 1; i <= n; i++)
        {
            sum += 0.4663;
        }
    }
    else
    {
        for (int i = 1; i <= n; i++)
        {
            sum += 0.5663;
        }
    }
    printf("%.1f\n", sum);
    return 0;
}

为什么只有二十分？