#include <stdio.h>
int main()
{
    int m,t,s,y,flag;
    scanf("%d%d%d",&m,&t,&s);
    if(m<=100&&t>0&&t<=100&&s<=1000) y=m-s/t;
    flag=s%t;
    if(flag!=0) 
    {printf("%d",y-1);}
    else
        printf("%d",y);
    return 0;
}