Rightmost Digit

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others)
Total Submission(s): 57447 Accepted Submission(s): 21742

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
2
3
4

Sample Output
7
6

Hint

In the first case, 3 * 3 * 3 = 27, so the rightmost digit is 7.
In the second case, 4 * 4 * 4 * 4 = 256, so the rightmost digit is 6.

思路

1、其實這個題目考察應該是快速冪取餘演算法，不過我並沒有用這個，我直接用暴力打表，找規律。感覺效率這個更高。

2、暴力打表方法這篇部落格我已經闡述—–暴力打表方法blog

程式碼

#include <iostream>
#include <stdio.h>
#include <math.h>
using namespace std;
int main()
{
    int t;
    int a[20]={1,4,7,6,5,6,3,6,9,0,1,6,3,6,5,6,7,4,9,0};
    cin>>t;
    while
 
(t--)
    {
        int n;
        int sum;
        cin>>n;
        sum=(n-1)%20;
        cout<<a[sum]<<endl;
    }
    return 0;
}