Data update

Task/Leap-year/Koka/leap-year-1.koka

@@ -0,0 +1,2 @@
+ pub fun is-leap-year(year: int)
+   year % 4 == 0 && (year % 100 != 0 || year % 400 == 0)

Task/Leap-year/Koka/leap-year-2.koka

@@ -0,0 +1,2 @@
+ pub fun is-leap-year'(year: int)
+   year % (if year % 100 == 0 then 400 else 4) == 0

Task/Leap-year/Koka/leap-year-3.koka

@@ -0,0 +1,6 @@
+ import std/time
+ import std/time/date
+ import std/time/time
+
+ pub fun is-leap-year''(year: int)
+   Date(year, 2, 28).time.add-days(1).day == 29

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

@@ -1,5 +1 @@
-is_leap() {
-  local year=$(( 10#${1:?'Missing year'} ))
-  (( year % 4 == 0 && ( year % 100 != 0 || year % 400 == 0 ) )) && return 0
-  return 1
-}
+is_leap() (( year=${1-0}, year % 4 == 0 && ( year % 100 != 0 || year % 400 == 0 )))

Task/Leap-year/YAMLScript/leap-year.ys

@@ -0,0 +1,16 @@
+!yamlscript/v0
+
+defn main(year):
+  say: "$year is $when-not(leap-year(year) 'not ')a leap year."
+
+# Either one works:
+
+defn leap-year(year):
+  ((year % 4) == 0) && (((year % 100) > 0) || ((year % 100) == 0))
+
+defn leap-year(year):
+  and:
+    zero?: (year % 4)
+    or:
+      pos?: (year % 100)
+      zero?: (year % 400)

Task/Leap-year/Zig/leap-year-2.zig

@@ -0,0 +1,35 @@
+/// The type that holds the current year, i.e. 2016
+pub const Year = u16;
+
+/// Returns true for years with 366 days
+/// and false for years with 365 days.
+pub fn isLeapYear(year: Year) bool {
+    // In the western Gregorian Calendar leap a year is
+    // a multiple of 4, excluding multiples of 100, and
+    // adding multiples of 400. In code:
+    //
+    // if (@mod(year, 4) != 0)
+    //     return false;
+    // if (@mod(year, 100) != 0)
+    //     return true;
+    // return (0 == @mod(year, 400));
+
+    // The following is equivalent to the above
+    // but uses bitwise operations when testing
+    // for divisibility, masking with 3 as test
+    // for multiples of 4 and with 15 as a test
+    // for multiples of 16. Multiples of 16 and
+    // 100 are, conveniently, multiples of 400.
+    const mask: Year = switch (year % 100) {
+        0 => 0b1111,
+        else => 0b11,
+    };
+    return 0 == year & mask;
+}
+
+test "isLeapYear" {
+    try testing.expectEqual(false, isLeapYear(2095));
+    try testing.expectEqual(true, isLeapYear(2096));
+    try testing.expectEqual(false, isLeapYear(2100));
+    try testing.expectEqual(true, isLeapYear(2400));
+}