Find out which date is earlier in C

In this article, we have explained the approach to check which date comes earlier among two dates (in format DD:MM:YYYY) and implemented this approach in C Programming Language.

Table of contents:

1. Problem Statement
2. Approach
3. Implementation in C
4. Output

Problem Statement

In this problem, we have to implement a program in C Programming Language which takes 2 dates as input and output is the date which comes earlier/ first.

The dates will be in format DD:MM:YYYY.

For example, if the two dates are:

Date 1: 21:03:2009
Date 2: 19:02:2019

Then, date 1 comes first (21/03/2009).

Approach

The approach to check which date is earlier is as follows:

1. The date format is in the form DD:MM:YYYY where DD is the date, MM is the month and YYYY is the year.
2. Take 2 dates as input in the above format.
3. If the year (YYYY) of the first date is less than the year of second date, then the first date comes first.
4. Else if the year (YYYY) of the first date is greater than the year of second date, then the second date comes first.
5. Else if the month (MM) of the first date is less than the month of the second date, then the first date comes first.
6. Else if the month (MM) of the first date is greater than the month of the second date, then the second date comes first.
7. Else if the date (DD) of the first date is less than the date of the second date, then the first date comes first.
8. Else if the date (DD) of the first date is greater than the date of the second date, then the second date comes first.

Implementation in C

Following is the implementation in C programming language:

#include<stdio.h>
int main()
{
	int a,b,c,d,e,f;
	printf("Enter the first date=");
	scanf("%d%d%d",&a,&b,&c);
	printf("Enter the second date=");
	scanf("%d%d%d",&d,&e,&f);
	if(c>f)
	{
		printf("%d/%d/%d is earlier",d,e,f);
	}
	else if(c<f)
	{
		printf("%d/%d/%d is earlier",a,b,c);
	}
	else if(b<e)
	{
		printf("%d/%d/%d is earlier",a,b,c);
	}
	else if(b>e)
	{
		printf("%d/%d/%d is earlier",d,e,f);
	}
	else if(a<d)
	{
		printf("%d/%d/%d is earlier",a,b,c);
	}
	else
	{
		printf("%d/%d/%d is earlier",d,e,f);
	}
	return 0;
}

Output

Following is the command to compile and run the above C program:

gcc opengenus.c
./a.out

Sample input:

23
11
2012
23
07
2012

Output:

23/7/2012 is earlier

With this article at OpenGenus, you must have the complete idea of how to check which date comes earlier.