#include<stdio.h>

int main()
{
    double x;
    while(scanf("%lf", &x) != EOF)
    {
        double y = 1-x/100;
        double z = 1;
        int i;
        for(i = 1; ; i++)
        {
            z = z*0.98;
            if(z <= y)
            {
                break;
            }
        }
        printf("%d\n", i);
    }
    return 0;
}