HDUOJ 6441 Find Integer
Problem Description
people in USSS love math very much, and there is a famous math problem .
give you two integers n,a,you are required to find 2 integers b,c such that a n + b n = c n a^n+b^n=c^n an+bn=cn.
Input
one line contains one integer T;(1≤T≤1000000)
next T lines contains two integers n,a;(0≤n≤1000,000,000,3≤a≤40000)
Output
print two integers b,c if b,c exits;(1≤b,c≤1000,000,000);
else print two integers -1 -1 instead.
Sample Input
1
2 3
Sample Output
4 5
Thinking questions~
First, according to Fermat's Last Theorem, when n> 2 n>2n>When 2 , there must be no positive integer solution ~
whenn = 0 n=0n=At 0 , there is obviously no solution ~
whenn = 1 n=1n=When 1 , output1 11 suma + 1 a + 1a+1 is enough,
whenn = 2 n=2n=At 2 o'clock, note that the title limit must be a positive integer, we consider parity, foraaa is odd,a 2 a^2a2 can be split intoa 2 ∗ 1 a^2*1a2∗1 ; toaaa is an even number,a 2 a^2a2 can be split intoa 2 2 ∗ 2 \frac{a^2}{2}*22a2∗2. Solve a binary linear equation separately~
pay attention to the output order, the AC code is as follows:
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
int T,n,a;
int main(){
scanf("%d",&T);
while(T--){
scanf("%d%d",&n,&a);
if(n>2||n==0) printf("-1 -1\n");
else if(n==2){
if(a%2) printf("%d %d\n",(a*a-1)/2,(a*a+1)/2);
else printf("%d %d\n",a*a/4-1,a*a/4+1);
}else if(n==1){
printf("1 %d\n",a+1);
}
}
return 0;
}