不要用键盘手敲题给数据、字符串，免得空格数量不对：

import java.util.*;
public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String[] str = {
                "200-OK",
                "202-Accepted",
                "400-Bad Request",
                "403-Forbidden",
                "404-Not Found",
                "500-Internal Server Error",
                "502-Bad Gateway"};
        Map<String, String> m = new HashMap<>();
        for(String s : str){
            String[] t = s.split("[-]");
            m.put(t[0], t[1]);
        }
        while (sc.hasNext()){
            System.out.println(m.get(sc.nextLine()));
        }
    }
}