LS 14 Square free（枚举）

Square free

Test whether n is square free. n is square free if and only if for all p>1 , p 2 is not divisors of n .

Input

The first line contains an integer t , the number of test cases.

The following n lines, each contains an integer n .

(1≤t≤10 2 ,1≤n≤10 18 )

Output

Print "Yes" if n is square free, or "No" otherwise.

Sample input

2
10
20

Sample output 1

Yes
No

思路： 只检查i^3<=n的数，那么最多检查10^6

            如果这个数是a*b*b 如果a>n那么b<n所以可以检查

           如果a<n 那么就把a剔除检查是否剔除完的数是平方数

           这样所有的情况就都包括在内了。

#include<iostream>
#include<cstring>
#include<cmath>
using namespace std;
const int mm=1000210;
int n;
bool p[mm];
int f[mm],pos;
int main()
{
  while(cin>>n)
  {
    while(n--)
    {
      long long m;
      cin>>m;
      bool yes=1;
      long long i;
      for(i=1;i*i*i<=m&&yes;i++)
        if(m%i==0)
      {
        long long z=m/i;
        long long y=(long long)sqrt(double(z)+0.01);
        if(y*y==z)yes=0;
        m/=i;
        if(i>1&&m%i==0)yes=0;
      }
      if(yes)cout<<"Yes\n";
      else cout<<"No\n";
    }
  }
}