Find day of the week for a given date

Write a function that calculates the day of the week for any particular date in the past or future. A typical application is to calculate the day of the week on which someone was born or some other special event occurred.

Recommended: Please solve it on “PRACTICE” first, before moving on to the solution.

Following is a simple function suggested by Sakamoto, Lachman, Keith and Craver to calculate day. The following function returns 0 for Sunday, 1 for Monday, etc.

C++

/* A program to find day of a given date */
#include <bits/stdc++.h> 
using namespace std; 
  
int dayofweek(int d, int m, int y)  
{  
    static int t[] = { 0, 3, 2, 5, 0, 3, 
                       5, 1, 4, 6, 2, 4 };  
    y -= m < 3;  
    return ( y + y / 4 - y / 100 +  
             y / 400 + t[m - 1] + d) % 7;  
}  
  
// Driver Code 
int main()  
{  
    int day = dayofweek(30, 8, 2010);  
    cout << day;  
  
    return 0;  
}  
  
// This is code is contributed  
// by rathbhupendra 

C

/* A program to find day of a given date */
#include<stdio.h> 
  
int dayofweek(int d, int m, int y) 
{ 
    static int t[] = { 0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4 }; 
    y -= m < 3; 
    return ( y + y/4 - y/100 + y/400 + t[m-1] + d) % 7; 
} 
  
/* Driver function to test above function */
int main() 
{ 
    int day = dayofweek(30, 8, 2010); 
    printf ("%d", day); 
  
    return 0; 
} 

Java

// A program to find day of a given date  
  
class GFG 
{ 
static int dayofweek(int d, int m, int y) 
{ 
    int t[] = { 0, 3, 2, 5, 0, 3, 5, 1, 4, 6, 2, 4 }; 
    y -= (m < 3) ? 1 : 0; 
    return ( y + y/4 - y/100 + y/400 + t[m-1] + d) % 7; 
} 
  
// Driver Program to test above function 
public static void main(String arg[]) 
{ 
    int day = dayofweek(30, 8, 2010); 
    System.out.print(day); 
} 
} 
  
// This code is contributed 
// by Anant Agarwal. 

Python3

# Python3 program to find day 
# of a given date 
  
def dayofweek(d, m, y): 
    t = [ 0, 3, 2, 5, 0, 3, 
          5, 1, 4, 6, 2, 4 ] 
    y -= m < 3
    return (( y + int(y / 4) - int(y / 100) 
             + int(y / 400) + t[m - 1] + d) % 7) 
  
# Driver Code 
day = dayofweek(30, 8, 2010) 
print(day) 
  
# This code is contributed by Shreyanshi Arun. 

C#

// C# program to find day of a given date  
using System; 
  
class GFG { 
      
    static int dayofweek(int d, int m, int y) 
    { 
        int []t = { 0, 3, 2, 5, 0, 3, 5,  
                            1, 4, 6, 2, 4 }; 
        y -= (m < 3) ? 1 : 0; 
          
        return ( y + y/4 - y/100 + y/400  
                         + t[m-1] + d) % 7; 
    } 
      
    // Driver Program to test above function 
    public static void Main() 
    { 
        int day = dayofweek(30, 8, 2010); 
          
        Console.Write(day);  
    } 
} 
  
// This code is contributed by Sam007. 

PHP

<?php 
// PHP program to find 
// day of a given date 
function dayofweek($d, $m, $y) 
{ 
    static $t = array(0, 3, 2, 5, 0, 3, 
                      5, 1, 4, 6, 2, 4); 
    $y -= $m < 3; 
    return ($y + $y / 4 - $y / 100 +  
            $y / 400 + $t[$m - 1] + $d) % 7; 
} 
  
// Driver Code 
$day = dayofweek(30, 8, 2010); 
echo $day; 
  
// This code is contributed by mits. 
?> 

Output : 1 (Monday)

See this for explanation of the above function.

References:
http://en.wikipedia.org/wiki/Determination_of_the_day_of_the_week

This article is compiled by Dheeraj Jain and reviewed by GeeksforGeeks team. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above

My Personal Notes

Recommended: Please solve it on “PRACTICE” first, before moving on to the solution.

C++

C

Java

Python3

C#

PHP

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