数据结构与算法分析1.8

问题描述：2^100(mod 5)是多少？

代码如下：

//1.8 2^100 (mod 5)#include <iostream>using namespace std;int pow(int m,int n,int d)//m^n mod d{    int index = 1;    int base = m%d;//when index = 1    while(index*2<=n){        index = index*2;        base = base*base%d;    }    while(++index<=n){        base=base*m%d;    }    return base;}int main(){    cout<<"2^4 mod 5:"<<pow(2,4,5)<<endl;    cout<<"3^4 mod 6:"<<pow(3,4,6)<<endl;    cout<<"2^5 mod 5:"<<pow(2,5,5)<<endl;    cout<<"2^6 mod 5:"<<pow(2,6,5)<<endl;    cout<<"2^7 mod 5:"<<pow(2,7,5)<<endl;    cout<<"2^100 mod 5:"<<pow(2,100,5)<<endl;    system("pause");}