Finite or not?(CF-#483 DIV2-C)(数论——GCD)

C. Finite or not?
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

You are given several queries. Each query consists of three integers ppqq and bb. You need to answer whether the result of p/qp/q in notation with base bb is a finite fraction.

A fraction in notation with base bb is finite if it contains finite number of numerals after the decimal point. It is also possible that a fraction has zero numerals after the decimal point.

Input

The first line contains a single integer nn (1n1051≤n≤105) — the number of queries.

Next nn lines contain queries, one per line. Each line contains three integers ppqq, and bb (0p10180≤p≤10181q10181≤q≤10182b10182≤b≤1018). All numbers are given in notation with base 1010.

Output

For each question, in a separate line, print Finite if the fraction is finite and Infinite otherwise.

Examples
input
Copy
2
6 12 10
4 3 10
output
Copy
Finite
Infinite
input
Copy
4
1 1 2
9 36 2
4 12 3
3 5 4
output
Copy
Finite
Finite
Finite
Infinite
Note

612=12=0,510612=12=0,510

43=1,(3)1043=1,(3)10

936=14=0,012936=14=0,012

412=13=0,13


首先恭喜杨哥哥在这次比赛中蓝名!!!,虽说有点(非常)妒忌,但是我也很开心,有人陪我打CF,还有人教我,

扫描二维码关注公众号,回复: 1014504 查看本文章

让我从黑名一步一步走出来,希望下一次就绿名。。。

题意:p/q   在b进制是否是一个  有限小数。

题解:这个题目有意思,

在杨哥哥的教导下,他说,首先对  分子分母约分,然后  再不断地对  b和q  /gcd(b,q);

主要看   q==1 证明有限,反之就说明  无限。

但是这样很很容易超时,  所以   b不断减少,减少它们间的差距来达到  优化。

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define gcd __gcd               //350(杨哥哥过的时间)
/*inline ll gcd(ll a,ll b){     //390
  while(b^=a^=b^=a%=b);
        return a;
}*/
/*inline ll gcd(ll a,ll b){     //420
    return a%b==0?b:gcd(b,a%b);
}*/
/*inline ll gcd(ll x,ll y){     //620
    ll i,j;
    if(x==0)return y;
    if(y==0)return x;
    for(i=0;0==(x&1);i++)x>>=1;
    for(j=0;0==(y&1);j++)y>>=1;
    if(j<i)i=j;
    while(1){
        if(x<y)x^=y,y^=x,x^=y;
        if(0==(x-=y))return y<<i;
        while(0==(x&1))x>>=1;
    }
}*/
int main()
{
    ll T,p,q,b;
    scanf("%lld",&T);
    while(T--){
        scanf("%lld%lld%lld",&p,&q,&b);
        ll t=gcd(p,q);
        q/=t;
        t=b;
        while(q!=1){
            t=gcd(q,t);
            q/=t;
            if(t==1)break;
        }
        if(q==1){
            printf("Finite\n");
        }else{
            printf("Infinite\n");
        }
    }
    return 0;
}

猜你喜欢

转载自blog.csdn.net/z_sea/article/details/80334032