diff --git a/Maths/ZellersCongruenceAlgorithm.js b/Maths/ZellersCongruenceAlgorithm.js
new file mode 100644
index 0000000000..728fc9cc16
--- /dev/null
+++ b/Maths/ZellersCongruenceAlgorithm.js
@@ -0,0 +1,26 @@
+// Zeller's Congruence Algorithm finds the day of the week from the Gregorian Date. Wikipedia: https://en.wikipedia.org/wiki/Zeller%27s_congruence
+export const zellersCongruenceAlgorithm = (day, month, year) => {
+ if (typeof day !== 'number' || typeof month !== 'number' || typeof year !== 'number') {
+ throw new TypeError('Arguments are not all numbers.')
+ }
+ const q = day
+ let m = month
+ let y = year
+ if (month < 3) {
+ m += 12
+ y -= 1
+ }
+ day =
+ (q + Math.floor(26 * (m + 1) / 10) + (y % 100) + Math.floor((y % 100) / 4) + Math.floor(Math.floor(y / 100) / 4) + (5 * Math.floor(y / 100))) %
+ 7
+ const days = [
+ 'Saturday',
+ 'Sunday',
+ 'Monday',
+ 'Tuesday',
+ 'Wednesday',
+ 'Thursday',
+ 'Friday'
+ ]
+ return days[day]
+}
diff --git a/Maths/test/ZellersCongruenceAlgorithm.test.js b/Maths/test/ZellersCongruenceAlgorithm.test.js
new file mode 100644
index 0000000000..931a9348a0
--- /dev/null
+++ b/Maths/test/ZellersCongruenceAlgorithm.test.js
@@ -0,0 +1,17 @@
+import { zellersCongruenceAlgorithm } from '../ZellersCongruenceAlgorithm'
+
+function testZeller (day, month, year, expected) {
+ test('Testing on ' + day + '/' + month + '/' + year, () => {
+ expect(zellersCongruenceAlgorithm(day, month, year)).toBe(expected)
+ })
+}
+
+test('Testing on this/should/throw', () => {
+ expect(() => {
+ zellersCongruenceAlgorithm('this', 'should', 'error')
+ }).toThrowError(new TypeError('Arguments are not all numbers.'))
+})
+testZeller(25, 1, 2013, 'Friday')
+testZeller(26, 1, 2013, 'Saturday')
+testZeller(16, 4, 2022, 'Saturday')
+testZeller(25, 4, 2022, 'Monday')
pFad - Phonifier reborn
Pfad - The Proxy pFad of © 2024 Garber Painting. All rights reserved.
Note: This service is not intended for secure transactions such as banking, social media, email, or purchasing. Use at your own risk. We assume no liability whatsoever for broken pages.
Alternative Proxies:
Alternative Proxy
pFad Proxy
pFad v3 Proxy
pFad v4 Proxy