题解 | #进制转换#

import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        while(sc.hasNext()){
            String str = sc.nextLine();
            str = str.substring(2);
            int n = str.length()-1;
            String[] arr = str.split("");
            int count = 0;
            for(int i = 0; i<n ; i++){
                count += convert(arr[i])*Math.pow(16,(n-i));
            }
            count += convert(arr[n]);
            System.out.println(count);
        }
        
    }
    
    private static int convert(String str){
        switch(str){
            case "A" :
                return 10;
            case "B" :
                return 11;
            case "C" :
                return 12;
            case "D" :
                return 13;
            case "E" :
                return 14;
            case "F" :
                return 15;
            default :
                return Integer.parseInt(str);
        }
            

    }
}