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# Program to convert time from 12 hour to 24 hour format

• Difficulty Level : Easy
• Last Updated : 18 Mar, 2023

Given a time at 12-hour AM/PM format, convert it to military (24-hour) time.
Note: Midnight is 12:00:00 AM on a 12-hour clock and 00:00:00 on a 24-hour clock. Noon is 12:00:00 PM on 12-hour clock and 12:00:00 on 24-hour clock

Examples:

```Input : A single string containing a time in 12-hour
clock format(hh:mm:ss AM or hh:mm:ss PM
where 01 <= hh <= 12 or 01 <= mm,ss <= 59
Output :Convert and print the given time in 24-hour format,
where 00 <= hh <= 23

Input : 07:05:45PM
Output : 19:05:45```

## C++

 `// C++ program to convert 12 hour to 24 hour` `// format` `#include` `using` `namespace` `std;`   `void` `print24(string str)` `{` `    ``// Get hours` `    ``int` `h1 = (``int``)str[1] - ``'0'``;` `    ``int` `h2 = (``int``)str[0] - ``'0'``;` `    ``int` `hh = (h2 * 10 + h1 % 10);`   `    ``// If time is in "AM"` `    ``if` `(str[8] == ``'A'``)` `    ``{` `        ``if` `(hh == 12)` `        ``{` `            ``cout << ``"00"``;` `            ``for` `(``int` `i=2; i <= 7; i++)` `                ``cout << str[i];` `        ``}` `        ``else` `        ``{` `            ``for` `(``int` `i=0; i <= 7; i++)` `                ``cout << str[i];` `        ``}` `    ``}`   `    ``// If time is in "PM"` `    ``else` `    ``{` `        ``if` `(hh == 12)` `        ``{` `            ``cout << ``"12"``;` `            ``for` `(``int` `i=2; i <= 7; i++)` `                ``cout << str[i];` `        ``}` `        ``else` `        ``{` `            ``hh = hh + 12;` `            ``cout << hh;` `            ``for` `(``int` `i=2; i <= 7; i++)` `                ``cout << str[i];` `        ``}` `    ``}` `}`   `// Driver code` `int` `main()` `{` `   ``string str = ``"07:05:45PM"``;` `   ``print24(str);` `   ``return` `0;` `}`

## Java

 `// Java program to convert 12 hour ` `// format to  24 hour format` `import` `java.io.*;` `public` `class` `GFG` `{` `static` `void` `print24(String str)` `{` `    ``// Get hours` `    ``int` `h1 = (``int``)str.charAt(``1``) - ``'0'``;` `    ``int` `h2 = (``int``)str.charAt(``0``) - ``'0'``;` `    ``int` `hh = (h2 * ``10` `+ h1 % ``10``);`   `    ``// If time is in "AM"` `    ``if` `(str.charAt(``8``) == ``'A'``)` `    ``{` `        ``if` `(hh == ``12``)` `        ``{` `            ``System.out.print(``"00"``);` `            ``for` `(``int` `i = ``2``; i <= ``7``; i++)` `                ``System.out.print(str.charAt(i));` `        ``}` `        ``else` `        ``{` `            ``for` `(``int` `i = ``0``; i <= ``7``; i++)` `                ``System.out.print(str.charAt(i));` `        ``}` `    ``}`   `    ``// If time is in "PM"` `    ``else` `    ``{` `        ``if` `(hh == ``12``)` `        ``{` `            ``System.out.print(``"12"``);` `            ``for` `(``int` `i = ``2``; i <= ``7``; i++)` `                ``System.out.print(str.charAt(i));` `        ``}` `        ``else` `        ``{` `            ``hh = hh + ``12``;` `            ``System.out.print(hh);` `            ``for` `(``int` `i = ``2``; i <= ``7``; i++)` `                ``System.out.print(str.charAt(i));` `        ``}` `    ``}` `} `   `// Driver code ` `public` `static` `void` `main (String[] args)` `{` `    ``String str = ``"07:05:45PM"``;` `    ``print24(str);` `}` `}`   `// This code is contributed by Anant Agarwal.`

## Python3

 `# Python3 program to convert 12` `# hour to 24 hour format` `def` `print24(s):`   `    ``# Get hours` `    ``h1 ``=` `ord``(s[``1``]) ``-` `ord``(``'0'``)` `    ``h2 ``=` `ord``(s[``0``]) ``-` `ord``(``'0'``)` `    ``hh ``=` `(h2 ``*` `10` `+` `h1 ``%` `10``)` ` `  `    ``# If time is in "AM"` `    ``if` `(s[``8``] ``=``=` `'A'``):` `        ``if` `(hh ``=``=` `12``):` `            ``print``(``'00'``, end ``=` `'')` `            `  `            ``for` `i ``in` `range``(``2``, ``8``):` `                ``print``(s[i], end ``=` `'')`   `        ``else``:` `            ``for` `i ``in` `range``(``0``, ``8``):` `                ``print``(s[i], end ``=` `'')` ` `  `    ``# If time is in "PM"` `    ``else``:` `        ``if` `(hh ``=``=` `12``):` `            ``print``(``"12"``, end ``=` `'')` `            `  `            ``for` `i ``in` `range``(``2``, ``8``):` `                ``print``(s[i], end ``=` `'')` `        `  `        ``else``:` `            ``hh ``=` `hh ``+` `12``;` `            ``print``(hh, end ``=` `'')` `            `  `            ``for` `i ``in` `range``(``2``, ``8``):` `                ``print``(s[i], end ``=` `'')` `            `  `# Driver code           ` `if` `__name__``=``=``"__main__"``:`   `   ``s ``=` `"07:05:45PM"` `   `  `   ``print24(s)` `   `  `# This code is contributed by rutvik_56`

## C#

 `// C# program to convert 12 hour ` `// format to 24 hour format` `using` `System;`   `class` `GFG` `{` `    `  `static` `void` `print24(String str)` `{` `    ``// Get hours` `    ``int` `h1 = (``int``)str[1] - ``'0'``;` `    ``int` `h2 = (``int``)str[0] - ``'0'``;` `    ``int` `hh = (h2 * 10 + h1 % 10);`   `    ``// If time is in "AM"` `    ``if` `(str[8] == ``'A'``)` `    ``{` `        ``if` `(hh == 12)` `        ``{` `            ``Console.Write(``"00"``);` `            ``for` `(``int` `i = 2; i <= 7; i++)` `                ``Console.Write(str[i]);` `        ``}` `        ``else` `        ``{` `            ``for` `(``int` `i = 0; i <= 7; i++)` `                ``Console.Write(str[i]);` `        ``}` `    ``}`   `    ``// If time is in "PM"` `    ``else` `    ``{` `        ``if` `(hh == 12)` `        ``{` `            ``Console.Write(``"12"``);` `            ``for` `(``int` `i = 2; i <= 7; i++)` `                ``Console.Write(str[i]);` `        ``}` `        ``else` `        ``{` `            ``hh = hh + 12;` `            ``Console.Write(hh);` `            ``for` `(``int` `i = 2; i <= 7; i++)` `                ``Console.Write(str[i]);` `        ``}` `    ``}` `} `   `// Driver code ` `public` `static` `void` `Main(String[] args)` `{` `    ``String str = ``"07:05:45PM"``;` `    ``print24(str);` `}` `}`   `// This code is contributed by Rajput-Ji`

## Javascript

 ``

Output

`19:05:45`

Time Complexity: O(1)
Auxiliary Space: O(1)

Method 2: Using java Date

## Java

 `// Java program for the above approach` `import` `java.text.DateFormat;` `import` `java.text.ParseException;` `import` `java.text.SimpleDateFormat;` `import` `java.util.Date;`   `public` `class` `GFG {` `    ``public` `static` `String englishTime(String input)` `        ``throws` `ParseException` `    ``{`   `        ``// Format of the date defined in the input String` `        ``DateFormat dateFormat` `            ``= ``new` `SimpleDateFormat(``"hh:mm:ss aa"``);` `      `  `        ``// Change the pattern into 24 hour format` `        ``DateFormat format` `            ``= ``new` `SimpleDateFormat(``"HH:mm:ss"``);` `        ``Date time = ``null``;` `        ``String output = ``""``;` `      `  `        ``// Converting the input String to Date` `        ``time = dateFormat.parse(input);` `      `  `        ``// Changing the format of date ` `        ``// and storing it in` `        ``// String` `        ``output = format.format(time);` `        ``return` `output;` `    ``}`   `    ``// Driver Code` `    ``public` `static` `void` `main(String[] arg)` `        ``throws` `ParseException` `    ``{` `        ``System.out.println(englishTime(``"07:05:45 PM"``));` `    ``}` `}`

## Python3

 `# Python program for the above approach` `import` `datetime`     `def` `englishTime(``input``):` `    ``# Format of the date defined in the input String` `    ``dateFormat ``=` `datetime.datetime.strptime(``input``, ``"%I:%M:%S %p"``)`   `    ``# Change the pattern into 24 hour format` `    ``format` `=` `datetime.datetime.strftime(dateFormat, ``"%H:%M:%S"``)` `    ``return` `format`     `# Driver Code` `print``(englishTime(``"07:05:45 PM"``))`

Output

`19:05:45`

Time Complexity: O(1)
Auxiliary Space: O(1)

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