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Finding number of days between two dates using StringStream
• Last Updated : 11 Apr, 2020

Given two strings str1 and str2 which represent two dates, the task is to count the number of days between given two dates. Given that dates given are beyond 1971.

Examples:

Input: str1 = “2020-01-29”, str2 = “2020-01-30”
Output: 1
Explanation:
The number of days between 29th January and 30th January is 1.

Input: str1 = “1971-06-29”, str2 = “2019-06-23”
Output: 17526

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: The idea is to convert both the dates into its respective seconds. Since there are 86, 400 seconds in a day, the number of days between both the days can be found out by dividing the difference of seconds with 86, 400.

Below is the implementation of the above approach:

 `// C++ implementation of the above approach``#include ``#include ``#include ``using` `namespace` `std;`` ` `// Function to find the number of days``// between given two dates``int` `daysBetweenDates(string date1, string date2)``{``    ``stringstream ss(date1 + ``"-"` `+ date2);``    ``int` `year, month, day;``    ``char` `hyphen;`` ` `    ``// Parse the first date into seconds``    ``ss >> year >> hyphen >> month >> hyphen >> day;``    ``struct` `tm` `starttm = { 0, 0, 0, day,``                          ``month - 1, year - 1900 };``    ``time_t` `start = ``mktime``(&starttm);`` ` `    ``// Parse the second date into seconds``    ``ss >> hyphen >> year >> hyphen``        ``>> month >> hyphen >> day;``    ``struct` `tm` `endtm = { 0, 0, 0, day,``                        ``month - 1, year - 1900 };``    ``time_t` `end = ``mktime``(&endtm);`` ` `    ``// Find out the difference and divide it``    ``// by 86400 to get the number of days``    ``return` `abs``(end - start) / 86400;``}`` ` `// Driver code``int` `main()``{``    ``string str1 = ``"2019-09-12"``;``    ``string str2 = ``"2020-08-04"``;``    ``cout << daysBetweenDates(str1, str2);``    ``return` `0;``}`
Output:
```327
```

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