#include <stdio.h>

int main(){
	int x,y,z,room=0,mod=0;
	while(scanf("%d%d%d",&x,&y,&z)!=EOF)
	{
		room=(x-z)/(y+z);
		mod=x%(y+z);
		if(z<mod&&mod<(y+z))
		{
			room--;
		}
		printf("%d",room);
	}
	return 0;
}