Data commit

Task/Leap-year/UNIX-Shell/leap-year-1.sh

@@ -0,0 +1,3 @@
+is_leap() {
+  return $((${1%00} & 3))
+}

Task/Leap-year/UNIX-Shell/leap-year-2.sh

@@ -0,0 +1,6 @@
+leap() {
+  if expr $1 % 4 >/dev/null; then return 1; fi
+  if expr $1 % 100 >/dev/null; then return 0; fi
+  if expr $1 % 400 >/dev/null; then return 1; fi
+  return 0;
+}

Task/Leap-year/UNIX-Shell/leap-year-3.sh

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+leap() {
+  date -d "$1-02-29" >/dev/null 2>&1;
+}

Task/Leap-year/UNIX-Shell/leap-year-4.sh

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+is_leap() {
+  local year=$(( 10#${1:?'Missing year'} ))
+  (( year % 4 == 0 && ( year % 100 != 0 || year % 400 == 0 ) )) && return 0
+  return 1
+}

Task/Leap-year/UNIX-Shell/leap-year-5.sh

@@ -0,0 +1,3 @@
+leap() {
+  cal 02 $1 | grep -q 29
+}

Task/Leap-year/UNIX-Shell/leap-year.sh

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+#!/bin/bash
+
+is_leap_year ()  # Define function named is_leap_year
+{
+
+declare -i year=$1      # declare integer variable "year" and set it to function parm 1
+
+echo -n "$year ($2)-> " # print the year passed in, but do not go to the next line
+
+if (( $year % 4 == 0 )) # if year not dividable by 4, then not a leap year, % is the modulus operator
+then
+        if (( $year % 400 == 0 ))       # if century dividable by 400, is a leap year
+        then
+                echo "This is a leap year"
+        else
+                if (( $year % 100 == 0 )) # if century not divisible by 400, not a leap year
+                then
+                        echo "This is not a leap year"
+                else
+                        echo "This is a leap year" # not a century boundary, but dividable by 4, is a leap year
+                fi
+        fi
+else
+        echo "This is not a leap year"
+fi
+
+
+}
+
+# test all cases
+# call the function is_leap_year several times with two parameters... year and test's expectation for 'is/not leap year.
+is_leap_year 1900 not # a leap year
+is_leap_year 2000 is  # a leap year
+is_leap_year 2001 not # a leap year
+is_leap_year 2003 not # a leap year
+is_leap_year 2004 is  # a leap year
+
+# Save the above to a file named is_leap_year.sh, then issue the following command to run the 5 tests of the function
+# bash is_leap_year.sh