A. Deadline,数论分块

Educational Codeforces Round 80 (Rated for Div. 2) A. Deadline

https://codeforces.com/contest/1288/problem/A
思路： $\lceil \frac{d}{x+1} \rceil=\lfloor\frac{d+x}{x+1}\rfloor=1+\lfloor\frac{d-1}{x+1}\rfloor$，直接数论分块求出最小值即可
其他解法见：https://blog.csdn.net/xing_mo/article/details/103982101

#include<bits/stdc++.h>
using namespace std;
int n,d;
int main()
{
	int t;
	scanf("%d",&t);
	while(t--)
	{
		scanf("%d%d",&n,&d);
		--d;
		int minn = 1e9+5;
		if(d == 0)
			minn = 1;
		for(int l = 1,r;l <= d;l = r+1)
		{
			r = d/(d/l);
			minn = min(minn,l+d/l);
		}
		if(minn <= n)
			printf("YES\n");
		else
			printf("NO\n");
	}
	return 0;
}