题解 | #进制转换#

import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

/**
 * @ProjectName: leetcode
 * @Package: com.company.niuke
 * @ClassName: SysConvert
 * @Author: Administrator
 * @Description: 进制转换
 * @Date: 2022/2/11 23:13
 * @Version: 1.0
 */
public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Map<Character, Integer> map = new HashMap<>();
        map.put('A',10);
        map.put('B',11);
        map.put('C',12);
        map.put('D',13);
        map.put('E',14);
        map.put('F',15);
        while (scanner.hasNext()) {
            String s = scanner.nextLine(); //十六进制数
            char[] ox = s.replace("0x", "").toUpperCase().toCharArray();
            int result = 0;
            for (int i = ox.length-1; i >= 0; i--) {
                if(map.containsKey(ox[i])) {
                    result += map.get(ox[i]) * Math.pow(16,ox.length-1-i);
                }else {
                    result += Integer.valueOf(String.valueOf(ox[i])) * Math.pow(16,ox.length-1-i);
                }
            }
            System.out.println(result);
        }
    }
}