循环结构

#include<stdio.h>
int main()
{
    int n,i;
    float k,a,b;
    while(scanf("%d%f",&n,&k)!=EOF){
        a=200;        
        b=(k/100)+1;
        i=1;    
        while(n*i<a&&i<21)
        {
            a*=b;
            i++;
        }
        if(i<21)
            printf("%d\n",i);
        else
            printf("Impossible\n");
    }
}