benchmark.zig

const std = @import("std");
const os = std.os;

pub fn main() void {
    const filename = std.mem.span(os.argv[1]);

    const open_result = os.open(filename, os.O_RDONLY, 0) catch unreachable;
    const fstat_result = os.fstat(open_result) catch unreachable;
    const data = os.mmap(null, @intCast(u64, fstat_result.size), os.PROT_READ, os.MAP_PRIVATE, open_result, 0) catch unreachable;

    var count: i32 = 0;
    var i: usize = 0;
    while (i < fstat_result.size - 1) : (i += 6) {
        var ints = [_]u8{0} ** 6;
        var j: usize = 0;
        while (j < 5) : (j += 1) {
            ints[data[i + j] - '1'] += 1;
            if (ints[data[i + j] - '1'] >= 3) {
                count += 1;
                break;
            }
        }
    }

    const stdout = std.io.getStdOut().outStream();
    stdout.print("{}", .{count}) catch unreachable;
}