Done with day 1!!!

Signed-off-by: jmug <u.g.a.mariano@gmail.com>

src/day01-1.zig

@@ -0,0 +1,61 @@
+const std = @import("std");
+const print = std.debug.print;
+const process = std.process;
+const fs = std.fs;
+
+fn bubble_sort(arr: []i32) void {
+    var switched = true;
+    while (switched) {
+        switched = false;
+        for (1..arr.len) |i| {
+            if (arr[i - 1] > arr[i]) {
+                arr[i] ^= arr[i - 1];
+                arr[i - 1] ^= arr[i];
+                arr[i] ^= arr[i - 1];
+                switched = true;
+            }
+        }
+    }
+}
+
+pub fn main() !void {
+    var args = process.args();
+    defer args.deinit();
+
+    // Skip the first argument since it's the name of the program.
+    _ = args.skip();
+
+    const rel_input_path: [:0]const u8 = args.next() orelse {
+        print("Provide the input file path\n", .{});
+        process.exit(1);
+    };
+
+    var abs_input_path_buff: [fs.max_path_bytes]u8 = undefined;
+    const input_path = try fs.realpath(rel_input_path, &abs_input_path_buff);
+    print("Input file path: {s}\n", .{input_path});
+
+    const input_file = try fs.openFileAbsolute(input_path, fs.File.OpenFlags{ .mode = .read_only });
+    defer input_file.close();
+
+    var item_count: u16 = 0;
+    var l_list: [1000]i32 = undefined;
+    var r_list: [1000]i32 = undefined;
+
+    const input_reader = input_file.reader();
+    var line_buf: [64]u8 = undefined;
+    while (try input_reader.readUntilDelimiterOrEof(&line_buf, ' ')) |first_str| {
+        defer item_count += 1;
+        l_list[item_count] = try std.fmt.parseInt(i32, first_str, 10);
+
+        const second_str = try input_reader.readUntilDelimiterOrEof(&line_buf, '\n');
+        r_list[item_count] = try std.fmt.parseInt(i32, std.mem.trim(u8, second_str.?, " "), 10);
+    }
+    bubble_sort(l_list[0..item_count]);
+    bubble_sort(r_list[0..item_count]);
+
+    var distance: u64 = 0;
+    for (0..item_count) |i| {
+        distance += @abs(l_list[i] - r_list[i]);
+    }
+    print("The answer is: {d}\n", .{distance});
+}

src/day01-2.zig

@@ -0,0 +1,57 @@
+const std = @import("std");
+const print = std.debug.print;
+const process = std.process;
+const fs = std.fs;
+
+pub fn main() !void {
+    var args = process.args();
+    defer args.deinit();
+
+    // Skip the first argument since it's the name of the program.
+    _ = args.skip();
+
+    const rel_input_path: [:0]const u8 = args.next() orelse {
+        print("Provide the input file path\n", .{});
+        process.exit(1);
+    };
+
+    var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
+    defer arena.deinit();
+    const allocator = arena.allocator();
+
+    var abs_input_path_buff: [fs.max_path_bytes]u8 = undefined;
+    const input_path = try fs.realpath(rel_input_path, &abs_input_path_buff);
+    print("Input file path: {s}\n", .{input_path});
+
+    const input_file = try fs.openFileAbsolute(input_path, fs.File.OpenFlags{ .mode = .read_only });
+    defer input_file.close();
+
+    var item_count: u16 = 0;
+    var l_list: [1000]i32 = undefined;
+    var r_list: [1000]i32 = undefined;
+
+    const input_reader = input_file.reader();
+    var line_buf: [64]u8 = undefined;
+    while (try input_reader.readUntilDelimiterOrEof(&line_buf, ' ')) |first_str| {
+        defer item_count += 1;
+        l_list[item_count] = try std.fmt.parseInt(i32, first_str, 10);
+
+        const second_str = try input_reader.readUntilDelimiterOrEof(&line_buf, '\n');
+        r_list[item_count] = try std.fmt.parseInt(i32, std.mem.trim(u8, second_str.?, " "), 10);
+    }
+
+    var r_hash = std.AutoHashMap(i32, i32).init(allocator);
+    defer r_hash.deinit();
+
+    for (0..item_count) |i| {
+        const num = r_list[i];
+        try r_hash.put(num, 1 + (r_hash.get(num) orelse 0));
+    }
+
+    var similarity: i64 = 0;
+    for (0..item_count) |i| {
+        const num = l_list[i];
+        similarity += num * (r_hash.get(num) orelse 0);
+    }
+    print("The answer is: {d}\n", .{similarity});
+}

src/day01.example.txt

@@ -0,0 +1,6 @@
+3   4
+4   3
+2   5
+1   3
+3   9
+3   3