#include <stdio.h>
#include <math.h>
int main(){
int n,h,m,sum;
while(scanf("%d %d %d",&n,&h,&m)!=EOF){
if(m%h){
printf("%d",n-m/h-1);
}
else printf("%d",n-m/h);
}
return 0;
}
#include <math.h>
int main(){
int n,h,m,sum;
while(scanf("%d %d %d",&n,&h,&m)!=EOF){
if(m%h){
printf("%d",n-m/h-1);
}
else printf("%d",n-m/h);
}
return 0;
}