346E - Doodle Jump - CodeForces Solution

#include<bits/stdc++.h>
using namespace std;
int T,a,n,p,h;
int calc(int a,int n,int p){
	int x=1ll*a*n/p;
	if (!x) return a>p-a*n?a:p-a*n;
	return calc(a-p%a,x-(1ll*a*n%p<(p/a-1)*a),a);
}
int main(){
	scanf("%d",&T);
	while(T--){
		scanf("%d%d%d%d",&a,&n,&p,&h); a%=p;
		printf("%s\n",((1ll*a*n<p?a:calc(a,n,p))>h)?"NO":"YES");
	}
}