hdu 5675 ztr loves math（数学技巧）

Problem Description

ztr loves research Math.One day,He thought about the "Lower Edition" of triangle equation set.Such as n=x2−y2.

He wanted to know that ,for a given number n,is there a positive integer solutions?

Input

There are T test cases.
The first line of input contains an positive integer T(T<=) indicating the number of test cases.

For each test case:each line contains a positive integer ,n<=.

Output

If there be a positive integer solutions,print True,else print False
 

Sample Input

Sample Output

False
True
True
True

Hint

For the fourth case,$ = ^{}-^{}$

 

给定nz，寻找是否存在一组(x,y)，满足x^2-y^2=n,那么我们可以构造两个方程 即（k+1）^2-k^2=n和（k+1）^2-(k-1)^2=n，得出结论，当n为奇数或者4的倍数时，方程一定有正整数解，但要记得特判1和4

 

AC代码：

 #include <iostream>
 #include <cstdio>
 #include <cstring>
 using namespace std;
 #define ll long long
 ll n;
 int main()
 {
     int t;
     scanf("%d",&t);
     while(t--){
        scanf("%I64d",&n);
        if(n== || n==){
           printf("False\n");
           continue;
        }
        if(n%== || n%==){
            printf("True\n");
        }else{
            printf("False\n");
        }
     }
     return ;
 }