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