const std = @import("std");


pub fn main() !void {
    var file = try std.fs.cwd().openFile("inputs/day1.txt", .{});
    defer file.close();

    var buf_reader = std.io.bufferedReader(file.reader());
    var in_stream = buf_reader.reader();

    var buf: [1024]u8 = undefined;
    var elf_sums: [1024]i32 = [_]i32{0} ** 1024;
    var i: usize = 0;
    while (try in_stream.readUntilDelimiterOrEof(&buf, '\n')) |line| {
        if (line.len == 0) {
            i += 1;
        }
        else {
            const calorie_count = std.fmt.parseInt(i32, line, 10) catch |err| {
                std.debug.print("Error converting str: {?}\n", .{err});
                return;
            };

            elf_sums[i] += calorie_count;
        }
    }


    std.sort.sort(i32, &elf_sums, {}, std.sort.desc(i32));

    var sum: i32 = 0;
    for (elf_sums[0..3]) |value, index| {
        std.debug.print("Pos {} = {}\n", .{index+1, value});
        sum += value;
    }

    std.debug.print("Total calories of the top three elves: {}\n", .{sum});
}

test "simple test" {
    var list = std.ArrayList(i32).init(std.testing.allocator);
    defer list.deinit(); // try commenting this out and see if zig detects the memory leak!
    try list.append(42);
    try std.testing.expectEqual(@as(i32, 42), list.pop());
}