Day 1 part 1

Author: gaborhermann

README.md

@@ -7,6 +7,6 @@
 Put the `input` file in the same directory as the code then compile and run it, e.g.:
 
 ```sh
-cd day01_part1
-zig run day01_part1.zig
+cd day01
+zig run part1.zig
 ```

day01/part1.zig

@@ -0,0 +1,28 @@
+const std = @import("std");
+
+pub fn main() !void {
+    var file = try std.fs.cwd().openFile("input", .{});
+    defer file.close();
+
+    var buf_reader = std.io.bufferedReader(file.reader());
+    var in_stream = buf_reader.reader();
+
+    var buf: [1024]u8 = undefined;
+
+    const first = try in_stream.readUntilDelimiterOrEof(&buf, '\n');
+    var prev: u32 = try std.fmt.parseInt(u32, first.?, 10);
+
+    var inc: u32 = 0;
+    while (try in_stream.readUntilDelimiterOrEof(&buf, '\n')) |line| {
+        if (line.len > 0) {
+            var x: u32 = try std.fmt.parseInt(u32, line, 10);
+            if (x > prev) {
+                inc += 1;
+            }
+            prev = x;
+        }
+    }
+
+    const stdout = std.io.getStdOut().writer();
+    try stdout.print("{d}\n", .{inc});
+}