Created
August 31, 2024 21:44
-
-
Save g-w1/681f97e78b24db23b646dab292b94e9b to your computer and use it in GitHub Desktop.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| const std = @import("std"); | |
| const buffer_size = 100_000_000; | |
| var m = std.mem.zeroes([buffer_size]u64); | |
| var default_prng = std.Random.DefaultPrng.init(0x420); | |
| pub fn main() void { | |
| const a = &m; | |
| var in: usize = 0; | |
| while (in < buffer_size) : (in += 1) { | |
| m[in] = default_prng.next(); | |
| } | |
| quicksort(a); | |
| assert_sorted(a); | |
| } | |
| fn assert_sorted(a: []u64) void { | |
| var i: usize = 0; | |
| while (i < a.len - 1) : (i += 1) { | |
| if (a[i] > a[i + 1]) { | |
| @panic("not sorted"); | |
| } | |
| } | |
| } | |
| fn quicksort(a: []u64) void { | |
| if (a.len > 1) { | |
| const p = partition(a); | |
| quicksort(a[0..p]); | |
| quicksort(a[p..a.len]); | |
| } | |
| } | |
| fn partition(a: []u64) usize { | |
| const part_val = a[a.len - 1]; | |
| var i: usize = 0; | |
| var j: usize = 0; | |
| while (j < a.len) { | |
| if (a[j] <= part_val) { | |
| swap(a, i, j); | |
| i += 1; | |
| } | |
| j += 1; | |
| } | |
| return i - 1; // the last elements are after the partition, so we want to keep them this way | |
| } | |
| fn swap(a: []u64, i: usize, j: usize) void { | |
| if (i != j) { | |
| const temp = a[i]; | |
| a[i] = a[j]; | |
| a[j] = temp; | |
| } | |
| } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment