zoukankan      html  css  js  c++  java
  • HDOJ 1097 A hard puzzle(循环问题)

    Problem Description
    lcy gives a hard puzzle to feng5166,lwg,JGShining and Ignatius: gave a and b,how to know the a^b.everybody objects to this BT problem,so lcy makes the problem easier than begin.
    this puzzle describes that: gave a and b,how to know the a^b’s the last digit number.But everybody is too lazy to slove this problem,so they remit to you who is wise.

    Input
    There are mutiple test cases. Each test cases consists of two numbers a and b(0< a,b<=2^30)

    Output
    For each test case, you should output the a^b’s last digit number.

    Sample Input
    7 66
    8 800

    Sample Output
    9
    6

    本题重要的是循环节的判断,java的大数会超时的。
    下面代码实现了循环节的寻找。

    import java.math.BigDecimal;
    import java.util.Scanner;
    
    public class Main {
        static int da[] = new int[10];
        public static void main(String[] args) {
            Scanner sc = new Scanner(System.in);
            dabiao();//打表
            while(sc.hasNext()){
                //超时
    //          BigDecimal a = sc.nextBigDecimal();
    //          int b = sc.nextInt();
    //          a = a.pow(b);
    //          String str = a.toString();
    //          System.out.println(str.charAt(str.length()-1));
    
                //找规律
                int a = sc.nextInt();
                int b = sc.nextInt();
                a = a%10;
                switch(a){
                case 0:System.out.println(da[0]);break;
                case 1:System.out.println(da[1]);break;
                case 2:System.out.println(shuchu(b,da[2],2));break;
                case 3:System.out.println(shuchu(b,da[3],3));break;
                case 4:System.out.println(shuchu(b,da[4],4));break;
                case 5:System.out.println(shuchu(b,da[5],5));break;
                case 6:System.out.println(shuchu(b,da[6],6));break;
                case 7:System.out.println(shuchu(b,da[7],7));break;
                case 8:System.out.println(shuchu(b,da[8],8));break;
                case 9:System.out.println(shuchu(b,da[9],9));break;
                }
    
            }
    
        }
    
        private static int shuchu(int b, int i, int j) {
            b=b%i;
            int sum=j;
            if(b==0){
                b=i;
            }
            for(int k=1;k<b;k++){
                sum=sum*j;
            }
            return sum%10;
        }
    
    
    
        private static void dabiao() {
            da[0]=0;
            da[1]=1;
    
            int h=0;
            for(int i=2;i<10;i++){
                h=0;
                for(int k=2;k<10;k++){
                    if(i==hm(k,i)){
                        h=k-1;
                        break;
                    }
                }
                da[i]=h;
            }
    
            //0-9的循环节输出
    //      for(int i=0;i<10;i++){
    //          System.out.println(da[i]);
    //      }
    
    
        }
    
        private static int hm(int k,int i) {
            int sum=1;
            for(int j=0;j<k;j++){
                sum=sum*i;
            }
            return sum%10;
        }
    
    
    }
    
  • 相关阅读:
    将新的rpm包添加到本地yum源
    linux cp命令直接覆盖不提示按Y/N的方法
    十一月二十一学习报告
    十一月二十学习报告
    十一月十九学习报告
    十一月十八学习报告
    十一月十七学习报告
    十一月十五学习报告
    十一月十四学习报告
    十一月十三学习报告
  • 原文地址:https://www.cnblogs.com/webmen/p/5739363.html
Copyright © 2011-2022 走看看