题解 | #进制转换#

import java.util.*;
public class Main{
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        while(in.hasNext()){
            String str = in.nextLine().substring(2).toLowerCase();
            int base = 16;
            int res=0;
            for(char ss:str.toCharArray()){
                int t=0;
                if(ss>='0' && ss<='9'){
                    t=ss-'0';
                }
                else if(ss>='a' && ss<='f'){
                    t=ss-'a'+10;
                }
                res=res*base+t;
            }
            System.out.println(res);
        }
    }
}