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# Difference between two given times

Given two times in string “HH:MM” format. Here ‘H’ shows hours and ‘M’ shows minutes. You have to find the difference in the same string format between these two strings. But both given strings should follow these cases.
1) Time 1 will be less than or equal to time2
2) Hours will be possible from 0 to 23.
3) Minutes will be possible from 0 to 59

Examples:

```Input : s1 = "14:00";
s2 = "16:45";
Output : result = "2:45"

Input : s1 = "1:04"
s2 = "13:05"
Output : result = "12:01"```

The idea is to first remove colon. After removing colon, hour difference can be computed using simple mathematics.

## C++

 `// C++ program to find difference between two``// given times.``#include ``using` `namespace` `std;` `// remove ':' and convert it into an integer``int` `removeColon(string s)``{``    ``if` `(s.size() == 4)``        ``s.replace(1, 1, ``""``);``    ` `    ``if` `(s.size() == 5)``        ``s.replace(2, 1, ``""``);``    ` `    ``return` `stoi(s);``}` `// Main function which finds difference``string diff(string s1, string s2)``{` `    ``// change string (eg. 2:21 --> 221, 00:23 --> 23)``    ``int` `time1 = removeColon(s1);``    ``int` `time2 = removeColon(s2);`` ` `    ``// difference between hours``    ``int` `hourDiff = time2 / 100 - time1 / 100 - 1;` `    ``// difference between minutes``    ``int` `minDiff = time2 % 100 + (60 - time1 % 100);` `    ``if` `(minDiff >= 60) {``        ``hourDiff++;``        ``minDiff = minDiff - 60;``    ``}` `    ``// convert answer again in string with ':'`` ` `    ``string res = to_string(hourDiff) + ``':'` `+ to_string(minDiff);``    ``return` `res;``}` `// Driver program to test above functions``int` `main()``{``    ``string s1 = ``"14:00"``;``    ``string s2 = ``"16:45"``;``    ``cout << diff(s1, s2) << endl;``    ``return` `0;``}`

## Java

 `/*package whatever //do not write package name here */``import` `java.io.*;` `class` `GFG``{``  ` `    ``// Java program to find difference between two``// given times.` `// remove ':' and convert it into an integer``static` `int` `removeColon(String s)``{``    ``if` `(s.length() == ``4``)``        ``s = s.substring(``0``,``1``) + s.substring(``2``);``    ` `    ``if` `(s.length() == ``5``)``        ``s = s.substring(``0``,``2``) + s.substring(``3``);``    ` `    ``return` `Integer.valueOf(s);``}` `// Main function which finds difference``static` `String diff(String s1, String s2)``{` `    ``// change string (eg. 2:21 --> 221, 00:23 --> 23)``    ``int` `time1 = removeColon(s1);``    ``int` `time2 = removeColon(s2);` `    ``// difference between hours``    ``int` `hourDiff = time2 / ``100` `- time1 / ``100` `- ``1``;` `    ``// difference between minutes``    ``int` `minDiff = time2 % ``100` `+ (``60` `- time1 % ``100``);` `    ``if` `(minDiff >= ``60``) {``        ``hourDiff++;``        ``minDiff = minDiff - ``60``;``    ``}` `    ``// convert answer again in string with ':'` `    ``String res = String.valueOf(hourDiff) + ``':'` `+ String.valueOf(minDiff);``    ``return` `res;``}``  ` `// Driver Code``public` `static` `void` `main(String args[])``{``    ``String s1 = ``"14:00"``;``    ``String s2 = ``"16:45"``;``    ``System.out.println(diff(s1, s2));``}``}` `// This code is contributed by shinjanpatra`

## Python3

 `# Python 3 program to find difference between two``# given times.` `# Remove ':' and convert it into an integer``def` `removeColon(s):``    ` `    ``if` `(``len``(s) ``=``=` `4``):``        ``s ``=` `s[:``1``] ``+` `s[``2``:]``    ` `    ``if` `(``len``(s) ``=``=` `5``):``        ``s ``=` `s[:``2``] ``+` `s[``3``:]``    ` `    ``return` `int``(s)` `# Main function which finds difference``def` `diff(s1, s2):``    ` `    ``# Change string``    ``# (eg. 2:21 --> 221, 00:23 --> 23)``    ``time1 ``=` `removeColon(s1)``    ``time2 ``=` `removeColon(s2)` `    ``# Difference between hours``    ``hourDiff ``=` `time2 ``/``/` `100` `-` `time1 ``/``/` `100` `-` `1``;` `    ``# Difference between minutes``    ``minDiff ``=` `time2 ``%` `100` `+` `(``60` `-` `time1 ``%` `100``)` `    ``if` `(minDiff >``=` `60``):``        ``hourDiff ``+``=` `1``        ``minDiff ``=` `minDiff ``-` `60` `    ``# Convert answer again in string with ':'``    ``res ``=` `str``(hourDiff) ``+` `':'` `+` `str``(minDiff)``    ` `    ``return` `res` `# Driver code``s1 ``=` `"14:00"``s2 ``=` `"16:45"` `print``(diff(s1, s2))` `# This code is contributed by ApurvaRaj`

## C#

 `// C# program to find difference between two``// given times.` `using` `System;` `class` `GFG {` `    ``// remove ':' and convert it into an integer``    ``static` `int` `removeColon(``string` `s)``    ``{``        ``if` `(s.Length == 4)``            ``s = s.Substring(0, 1) + s.Substring(2);` `        ``if` `(s.Length == 5)``            ``s = s.Substring(0, 2) + s.Substring(3);` `        ``return` `Convert.ToInt32(s);``    ``}` `    ``// Main function which finds difference``    ``static` `string` `diff(``string` `s1, ``string` `s2)``    ``{` `        ``// change string (eg. 2:21 --> 221, 00:23 --> 23)``        ``int` `time1 = removeColon(s1);``        ``int` `time2 = removeColon(s2);` `        ``// difference between hours``        ``int` `hourDiff = time2 / 100 - time1 / 100 - 1;` `        ``// difference between minutes``        ``int` `minDiff = time2 % 100 + (60 - time1 % 100);` `        ``if` `(minDiff >= 60) {``            ``hourDiff++;``            ``minDiff = minDiff - 60;``        ``}` `        ``// convert answer again in string with ':'` `        ``string` `res = Convert.ToString(hourDiff) + ``":"``                     ``+ Convert.ToString(minDiff);``        ``return` `res;``    ``}` `    ``// Driver Code``    ``public` `static` `void` `Main(``string``[] args)``    ``{``        ``string` `s1 = ``"14:00"``;``        ``string` `s2 = ``"16:45"``;``        ``Console.WriteLine(diff(s1, s2));``    ``}``}` `// This code is contributed by phasing17`

## Javascript

 ``

Output:

`2:45`

Time complexity: O(1), as the length of the string will be either 4 or 5, the operations performed by stoi and replace will be considered to be constant.
Auxiliary space: O(1)

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