HackerRank Time Conversion Problem Solution

In this post, We are going to solve HackerRankTime Conversion Problem.

Given a time in 12-hour AM/PM format, convert it to military (24-hour) time.

Note: – 12:00:00AM on a 12-hour clock is 00:00:00 on a 24-hour clock.

12:00:00PM on a 12-hour clock is 12:00:00 on a 24-hour clock.

Example

s = 12:01:00PM

Return ’12:01:00′

s = 12:01:00AM

Return ’00:01:00′.

Function Description

Complete the time conversion function in the editor below. It should return a new string representing the input time in 24-hour format.

time conversion has the following parameter(s):

string s: a time in 12-hour format

Returns

string: the time in 24-hour format

Constraints

All input times are valid

Sample Input 0

07:05:45PM

Sample Output 0

19:05:45

HackerRank Time Conversion Problem Solution

Time Conversion C Solution

#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

int main() {

    char input[15];
    int hours;
    int minutes;
    int seconds;
    int side;
    
    scanf("%s", input);
    
    if (input[8] == 'A'){
        side = 0;
    }
    else{
        side = 1;
    }
    
    
    hours = atoi(strtok(input, ":"));
    minutes = atoi(strtok(NULL, ":"));
    seconds = atoi(strtok(NULL, "AP"));
    
    if (side == 1){
        if (hours != 12){
            hours += 12;
        }
    }
    else if (hours == 12){
        hours = 0;
    }

    if (hours < 10){
        printf("0%d", hours);
    }
    else{
        printf("%d", hours);
    }
    
    printf(":");
    
    if (minutes < 10){
        printf("0%d", minutes);
    }
    else{
        printf("%d", minutes);
    }
    
    printf(":");
    
    if (seconds < 10){
        printf("0%d", seconds);
    }
    else{
        printf("%d", seconds);
    }
    
    
    return 0;
}

Time Conversion C++ Solution

#include <iostream>
#include <algorithm>

using namespace std;

int main()
{
    string time;
    cin >> time;

    std::transform(time.begin(), time.end(), time.begin(), ::toupper);

    if (time.find("AM") != string::npos) {
        time.erase(time.end() - 2, time.end());
        int hour = stoi(time.substr(0, 2));
        if (hour == 12) {
            time.replace(0, 2, "00");
        }

    } else if (time.find("PM") != string::npos) {
        time.erase(time.end() - 2, time.end());
        int hour = stoi(time.substr(0, 2));
        if (hour != 12) {
            hour = hour + 12;
        }

        time.replace(0, 2, to_string(hour));
    } else {
        cout << "Wrong 12H format\n";
        return 0;
    }

    cout << time << '\n';
    return 0;
}

Time Conversion C Sharp Solution

using System;
using System.Collections.Generic;
using System.IO;
class Solution {
    static void Main(String[] args) {
        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution */
        String s = Console.ReadLine();
        int hours = Int32.Parse(s.Substring(0,2));
        
        int mins = Int32.Parse(s.Substring(3,2));
        
        int secs = Int32.Parse(s.Substring(6,2));
        String half = s.Substring(8,2);
        if(half.CompareTo("AM")==0){
            if(hours==12) hours=0;
        }else{
            if(hours!=12) hours+=12;
        }
        String h = hours.ToString();
        String m = mins.ToString();
        String sc = secs.ToString();
        if(hours<10)
            h = "0"+h;
        if(mins<10)
            m = "0"+m;
        if(secs<10)
            sc = "0"+sc;
        Console.WriteLine(h+":"+m+":"+sc);
        
        //Console.WriteLine(mins);
    }
}

Time Conversion Java Solution

import java.io.*;
import java.math.*;
import java.security.*;
import java.text.*;
import java.util.*;
import java.util.concurrent.*;
import java.util.function.*;
import java.util.regex.*;
import java.util.stream.*;
import static java.util.stream.Collectors.joining;
import static java.util.stream.Collectors.toList;

class Result {

    /*
     * Complete the 'timeConversion' function below.
     *
     * The function is expected to return a STRING.
     * The function accepts STRING s as parameter.
     */

    static String timeConversion(String timeString) {
        if (timeString.charAt(8) == 'P') {

            String portion = timeString.substring(0, 8);
            String[] times = portion.split(":");
            if (times[0].matches("12")) {
                return times[0] + ":" + times[1] + ":" + times[2];
            }
            times[0] = String.valueOf(Integer.valueOf(times[0]) + 12);
            return times[0] + ":" + times[1] + ":" + times[2];
        } else {
            String portion = timeString.substring(0, 8);
            String[] times = portion.split(":");
            if (times[0].matches("12")) {
                times[0] = "00";
                return times[0] + ":" + times[1] + ":" + times[2];
            }
            return timeString.substring(0, 8);

        }
    }

}

public class Solution {
    public static void main(String[] args) throws IOException {
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        String s = bufferedReader.readLine();

        String result = Result.timeConversion(s);

        bufferedWriter.write(result);
        bufferedWriter.newLine();

        bufferedReader.close();
        bufferedWriter.close();
    }
}

Time Conversion JavaScript Solution

# Enter your code here. Read input from STDIN. Print output to STDOUT
import re
d = raw_input()
d_list = d.strip().split(":")
hh = int(d_list[0])
mm = int(d_list[1])
ap = re.findall(r'[A-Z]+',d_list[2])[0]
ss  = int(re.findall(r'[0-9]+',d_list[2])[0])
hhh = hh+12

if ap == 'AM' and hh <= 11:
    print ("%02d" %hh)+':'+("%02d" %mm)+':'+("%02d" %ss)
if ap =="AM" and hh == 12:
    print ("%02d" %0)+':'+("%02d" %mm)+':'+("%02d" %ss)
if ap == 'PM' and hh <= 11:
    print ("%02d" %hhh)+':'+("%02d" %mm)+':'+("%02d" %ss)
if ap == 'PM' and hh == 12:
    print ("%02d" %12)+':'+("%02d" %mm)+':'+("%02d" %ss)

Time Conversion Python Solution

i_time = input()
if i_time == '12:00:00AM':
    print('00:00:00')
    exit()

if i_time == '12:00:00PM':
    print('12:00:00')
    exit()

if i_time[8] == 'A':
    hour = int(i_time[:2])
    if hour == 12: hour = 0
    hour = "{:02.0f}".format(hour)
    print(str(hour)+i_time[2:8])
else:
    hour = int(i_time[:2])+12
    if hour == 24: hour = 12
    hour = "{:02.0f}".format(hour)
    print(str(hour)+i_time[2:8])

Other solutions

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