diff --git a/CMakeLists.txt b/CMakeLists.txt index 375a007341..e08a55002b 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -222,6 +222,7 @@ install(FILES "${CMAKE_SOURCE_DIR}/std/net.zig" DESTINATION "${ZIG_STD_DEST}") install(FILES "${CMAKE_SOURCE_DIR}/std/os.zig" DESTINATION "${ZIG_STD_DEST}") install(FILES "${CMAKE_SOURCE_DIR}/std/rand.zig" DESTINATION "${ZIG_STD_DEST}") install(FILES "${CMAKE_SOURCE_DIR}/std/rand_test.zig" DESTINATION "${ZIG_STD_DEST}") +install(FILES "${CMAKE_SOURCE_DIR}/std/sort.zig" DESTINATION "${ZIG_STD_DEST}") install(FILES "${CMAKE_SOURCE_DIR}/std/str.zig" DESTINATION "${ZIG_STD_DEST}") install(FILES "${CMAKE_SOURCE_DIR}/std/test_runner.zig" DESTINATION "${ZIG_STD_DEST}") install(FILES "${CMAKE_SOURCE_DIR}/std/test_runner_libc.zig" DESTINATION "${ZIG_STD_DEST}") diff --git a/std/index.zig b/std/index.zig index 0b7333b138..95d9e80e7c 100644 --- a/std/index.zig +++ b/std/index.zig @@ -4,6 +4,7 @@ pub const os = @import("os.zig"); pub const math = @import("math.zig"); pub const str = @import("str.zig"); pub const cstr = @import("cstr.zig"); +pub const sort = @import("sort.zig"); pub const net = @import("net.zig"); pub const list = @import("list.zig"); pub const hash_map = @import("hash_map.zig"); diff --git a/std/sort.zig b/std/sort.zig new file mode 100644 index 0000000000..af65cd3a59 --- /dev/null +++ b/std/sort.zig @@ -0,0 +1,111 @@ +const assert = @import("debug.zig").assert; +const str = @import("str.zig"); +const math = @import("math.zig"); + +pub const Cmp = math.Cmp; + +pub fn sort(inline T: type, array: []T, inline cmp: fn(a: T, b: T)->Cmp) { + if (array.len > 0) { + quicksort(T, array, 0, array.len - 1, cmp); + } +} + +fn quicksort(inline T: type, array: []T, left: usize, right: usize, inline cmp: fn(a: T, b: T)->Cmp) { + var i = left; + var j = right; + var p = (i + j) / 2; + + while (i <= j) { + while (cmp(array[i], array[p]) == Cmp.Less) { + i += 1; + } + while (cmp(array[j], array[p]) == Cmp.Greater) { + j -= 1; + } + if (i <= j) { + const tmp = array[i]; + array[i] = array[j]; + array[j] = tmp; + i += 1; + if (j > 0) j -= 1; + } + } + + if (left < j) quicksort(T, array, left, j, cmp); + if (i < right) quicksort(T, array, i, right, cmp); +} + +pub fn i32asc(a: i32, b: i32) -> Cmp { + return if (a > b) Cmp.Greater else if (a < b) Cmp.Less else Cmp.Equal; +} + +pub fn i32desc(a: i32, b: i32) -> Cmp { + return reverse(i32asc(a, b)); +} + +pub fn u8asc(a: u8, b: u8) -> Cmp { + return if (a > b) Cmp.Greater else if (a < b) Cmp.Less else Cmp.Equal; +} + +pub fn u8desc(a: u8, b: u8) -> Cmp { + return reverse(u8asc(a, b)); +} + +fn reverse(was: Cmp) -> Cmp { + return if (was == Cmp.Greater) Cmp.Less else if (was == Cmp.Less) Cmp.Greater else Cmp.Equal; +} + +// --------------------------------------- +// tests + +fn testSort() { + @setFnTest(this, true); + + const u8cases = [][][]u8 { + [][]u8{"", ""}, + [][]u8{"a", "a"}, + [][]u8{"az", "az"}, + [][]u8{"za", "az"}, + [][]u8{"asdf", "adfs"}, + [][]u8{"one", "eno"}, + }; + + for (u8cases) |case| { + sort(u8, case[0], u8asc); + assert(str.eql(case[0], case[1])); + } + + const i32cases = [][][]i32 { + [][]i32{[]i32{}, []i32{}}, + [][]i32{[]i32{1}, []i32{1}}, + [][]i32{[]i32{0, 1}, []i32{0, 1}}, + [][]i32{[]i32{1, 0}, []i32{0, 1}}, + [][]i32{[]i32{1, -1, 0}, []i32{-1, 0, 1}}, + [][]i32{[]i32{2, 1, 3}, []i32{1, 2, 3}}, + }; + + for (i32cases) |case| { + sort(i32, case[0], i32asc); + assert(str.sliceEql(i32, case[0], case[1])); + } +} + +fn testSortDesc() { + @setFnTest(this, true); + + const revCases = [][][]i32 { + [][]i32{[]i32{}, []i32{}}, + [][]i32{[]i32{1}, []i32{1}}, + [][]i32{[]i32{0, 1}, []i32{1, 0}}, + [][]i32{[]i32{1, 0}, []i32{1, 0}}, + [][]i32{[]i32{1, -1, 0}, []i32{1, 0, -1}}, + [][]i32{[]i32{2, 1, 3}, []i32{3, 2, 1}}, + }; + + for (revCases) |case| { + sort(i32, case[0], i32desc); + assert(str.sliceEql(i32, case[0], case[1])); + } + +} +