#include<stdio.h>
int main()
{
int n,h,m;
int sakura;//已经喝了的酸奶盒数
while(scanf("%d %d %d",&n,&h,&m)!=EOF)
{
if(m%h==0)
{
sakura=m/h;
printf("%d",n-sakura);
}
else
printf("%d",n-m/h-1);
}
return 0;
}