package com.company;import java.sql.Time;import java.text.DecimalFormat;import java.util.Calendar;import java.util.Date;import java.util.Scanner;public class Main {    public static void main(String[] args) {    // write your code here        Scanner sc=new Scanner(System.in);        int start=sc.nextInt();        int end=sc.nextInt();        int a=start/100;        int b=start%100;        int c=end/100;        int d=end%100;        int x,y;        DecimalFormat df=new DecimalFormat("00");        if(b<=d){            x=d-b;            y=c-a;        }else{            x=d+60-b;            y=c-a-1;        }        System.out.println(df.format(y)+":"+df.format(x));    }}

缺少分析，找方法找半天，还不如自己组装，此题百度过。