Find Leap Year with Different Methods in Php

What is Leap Year ?

A Year, occurred once every four years, which has 366 days , one additional day ( 29 February ) added to keep the calendar year synchronised with the astronomical or seasonal year.

Programs Functions

	//Method 1
	function leapyear_1($year) {
		// conditions to find out the leap year
		return (0 == $year % 4) ? true : false;
	}
	//Method 2
	function leapyear_2($year) {
		// conditions to find out the leap year
		if ((0 == $year % 4) && (0 != $year % 100) || (0 == $year % 400)) {
			return true;
		} else {
			return false;
		}
	}
	//Method 3
	function leapyear_3($year) {
		// conditions to find out the leap year
		return (date('L', mktime(0, 0, 0, 1, 1, $year))) ? true : false;
	}
	//Method 4
	function leapyear_4($year) {
		// conditions to find out the leap year
		return checkdate(2, 29, $year);
	}
	//Method 5
	function leapyear_5($year) {
		// conditions to find out the leap year
		$leap = date('L', mktime(0, 0, 0, 1, 1, $year));
		return $year.' '.($leap ? 'is' : 'is not').' a leap year.';
	}

Method  1

//Method 1
	function leapyear_1($year) {
		// conditions to find out the leap year
		return (0 == $year % 4) ? true : false;
	}
$year = 2020;
	if (leapyear_1($year)) {
		echo "$year is a Leap Year";
	} else {
		echo "$year is Not a Leap Year";
	}
//2020 is a Leap Year

Method  2

//Method 2
	function leapyear_2($year) {
		// conditions to find out the leap year
		if ((0 == $year % 4) && (0 != $year % 100) || (0 == $year % 400)) {
			return true;
		} else {
			return false;
		}
	}
$year = 2020;
	if (leapyear_2($year)) {
		echo "$year is a Leap Year";
	} else {
		echo "$year is Not a Leap Year";
	}
//2020 is a Leap Year

Method  3

	//Method 3
	function leapyear_3($year) {
		// conditions to find out the leap year
		return (date('L', mktime(0, 0, 0, 1, 1, $year))) ? true : false;
	}
	$year = 2020;
	if (leapyear_3($year)) {
		echo "$year is a Leap Year";
	} else {
		echo "$year is Not a Leap Year";
	}
	//2020 is a Leap Year

Method  4

	//Method 4
	function leapyear_4($year) {
		// conditions to find out the leap year
		return checkdate(2, 29, $year);
	}

	$year = 2020;
	if (leapyear_4($year)) {
		echo "$year is a Leap Year";
	} else {
		echo "$year is Not a Leap Year";
	}
	//2020 is a Leap Year

Method  5

//Method 5
	function leapyear_5($year) {
		// conditions to find out the leap year
		$leap = date('L', mktime(0, 0, 0, 1, 1, $year));
		return $year.' '.($leap ? 'is' : 'is not').' a leap year.';
	}
echo leapyear_5(2020); 
//2020 is a leap year.