`
Simone_chou
  • 浏览: 192759 次
  • 性别: Icon_minigender_2
  • 来自: 广州
社区版块
存档分类
最新评论

On Corruption and Numbers(数学)

    博客分类:
  • CF
 
阅读更多
B. On Corruption and Numbers
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Alexey, a merry Berland entrant, got sick of the gray reality and he zealously wants to go to university. There are a lot of universities nowadays, so Alexey is getting lost in the diversity — he has not yet decided what profession he wants to get. At school, he had bad grades in all subjects, and it's only thanks to wealthy parents that he was able to obtain the graduation certificate.

The situation is complicated by the fact that each high education institution has the determined amount of voluntary donations, paid by the new students for admission — ni berubleys. He cannot pay more than ni, because then the difference between the paid amount andni can be regarded as a bribe!

Each rector is wearing the distinctive uniform of his university. Therefore, the uniform's pockets cannot contain coins of denomination more than ri. The rector also does not carry coins of denomination less than li in his pocket — because if everyone pays him with so small coins, they gather a lot of weight and the pocket tears. Therefore, a donation can be paid only by coins of denomination xberubleys, where li ≤ x ≤ ri (Berland uses coins of any positive integer denomination). Alexey can use the coins of different denominations and he can use the coins of the same denomination any number of times. When Alexey was first confronted with such orders, he was puzzled because it turned out that not all universities can accept him! Alexey is very afraid of going into the army (even though he had long wanted to get the green uniform, but his dad says that the army bullies will beat his son and he cannot pay to ensure the boy's safety). So, Alexey wants to know for sure which universities he can enter so that he could quickly choose his alma mater.

Thanks to the parents, Alexey is not limited in money and we can assume that he has an unlimited number of coins of each type.

In other words, you are given t requests, each of them contains numbers ni, li, ri. For each query you need to answer, whether it is possible to gather the sum of exactly ni berubleys using only coins with an integer denomination from li to ri berubleys. You can use coins of different denominations. Coins of each denomination can be used any number of times.

Input

The first line contains the number of universities t, (1 ≤ t ≤ 1000) Each of the next t lines contain three space-separated integers:ni, li, ri (1 ≤ ni, li, ri ≤ 109li ≤ ri).

Output

For each query print on a single line: either "Yes", if Alexey can enter the university, or "No" otherwise.

Sample test(s)
input
2
5 2 3
6 4 5
output
Yes
No
Note

You can pay the donation to the first university with two coins: one of denomination 2 and one of denomination 3 berubleys. The donation to the second university cannot be paid.

 

 

     题意:

     给出T(1 ~ 1000)个case,每次给出N,L,R(1 <= N,L,R <= 10 ^ 9)代表有能不能由 L 到 R 内的数组成N。

 

     思路:

     数学。

     给出的 L 到 R 内的数如果每次只选择一个数,则能组成 L ~ R这么多的数;若每次选择两个数,则能组成 2 * L ~2 * R内的数;选择 K 个,则为 K * L ~ K * R 这么多的数。如果 N 属于 K 区间内的数,则能满足要求,若找不到一个K 满足 K * L <= N <= K * R,则不能满足要求。注意用long long 即可。

   

     AC:

#include<stdio.h>
int main()
{
    int t;
    scanf("%d",&t);
    while(t--)
    {
        __int64 n,l,r;
        scanf("%I64d%I64d%I64d",&n,&l,&r);
        if(r * (n / l) >= n)    printf("Yes\n");
        else                    printf("No\n");
    }
    return 0;
}

 

 

分享到:
评论

相关推荐

Global site tag (gtag.js) - Google Analytics