HDOJ 1061 Rightmost Digit（快速幂）

Rightmost Digit

Problem Description

Given a positive integer N, you should output the most right digit of N^N.

 

Input

The input contains several test cases. The first line of the input is a single integer T which is the number of test cases. T test cases follow.
Each test case contains a single positive integer N(1<=N<=1,000,000,000).

 

Output

For each test case, you should output the rightmost digit of N^N.

 

Sample Input

234

 

Sample Output

76

题目大意：给出一个数N，求N ^ N的最右一位

解题思路：快速幂，由于要求N ^ N个位数上的结果，所以可以求(N % 10) ^ N，再将结果对10取余即可。

代码如下：

#include <cstdio>typedef long long ll;ll mod_pow(ll x,ll n,ll mod){ll res = 1;while(n > 0){if(n & 1)res *= x % mod;x = x * x % mod;n >>= 1; }return res;}int main(){int t;ll n;scanf("%d",&t);while(t--){scanf("%lld",&n);printf("%d\n",mod_pow(n % 10,n,10) % 10);}return 0;}