题解 | 进制转换

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String numStr = in.nextLine();
        int num = 0;
        for(int i=2;i<numStr.length();i++){
            int d = 0;
            char c = numStr.charAt(i);
            if(c>='0' && c <='9'){
                d = c-'0';
            }else if(c>='A' && c<='F'){
                d = 10 + (c-'A');
            }
            num = (num << 4)|d;
        }
        System.out.println(num);
    }
}