Design a program that will receive a valid time in the 12-hour format (e. g. 11:05 PM) and convert it to its equivalent 24-hour format (e. g. 2305). Assume 0000 in 24-hour format is 12:00AM in 12-hour format. The program should continue accepting inputs until a sentinel value of 99:99AM is entered. Ex: If the input is:09:04AM 10:45AM 11:23AM 99:99AMthe output is:0904 1045 1123Hints:Use System. out. printf statements using "d" (Links to an external site.) to match output format. Use Integer. valueOf(s) (Links to an external site.), where s is a String variable, to covert String to int.

see explaination for program code

Explanation:

/Convert 12-hour time to 24-hour time format

import java.io.*;

public class Main

{

public static void main(String[] args) throws IOException {

BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

String str=br.readLine();

while(!str.equals("99:99AM")){

System.out.println(getConvertedTime(str));

str=br.readLine();

}

}

public static String getConvertedTime(String str){

String s=str.substring(str.length()-2);

String[] hoursAndMinutes=str.substring(0,5).split(":");

if(s.equals("AM")){

//if the time is in AM then we can use same hours and minutes except for 12th hour so we need

//special case for that if it is 12th hour we will use "00" instead of 12 for other we can use same hours

if(hoursAndMinutes[0].equals("12")) return "00"+hoursAndMinutes[1];

else return hoursAndMinutes[0]+hoursAndMinutes[1];

}

else{

//if the time is in PM we need to add hours to 12 unless the hour is 12 in case of 12 we need to keep it as it is

if(hoursAndMinutes[0].equals("12")) return "12"+hoursAndMinutes[1];

else{

int hours=Integer.valueOf(hoursAndMinutes[0]);

hoursAndMinutes[0]=String.valueOf(12+hours);

return hoursAndMinutes[0]+hoursAndMinutes[1];

}

}

}

}

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