1 files changed, 72 insertions, 0 deletions
diff --git a/src/day01.zig b/src/day01.zig
new file mode 100644
index 0000000..2010816
--- /dev/null
+++ b/src/day01.zig
@@ -0,0 +1,72 @@
+const std = @import("std");
+const print = std.debug.print;
+
+pub fn solve(part: []u8, reader: *std.Io.Reader, _: std.mem.Allocator) !void {
+    if (std.mem.eql(u8, part, "1")) {
+        try part1(reader);
+    } else {
+        try part2(reader);
+    }
+}
+
+fn part1(reader: *std.Io.Reader) !void {
+    var pos: i32 = 50;
+    var zero: usize = 0;
+    while (reader.takeDelimiterInclusive('\n')) |line| {
+        if (line.len == 0){
+            break;
+        }
+
+        const numSlice = std.mem.trimRight(u8, line[1..], &[_]u8{'\n'});
+        const rotations = try std.fmt.parseInt(i32, numSlice, 10);
+        if (line[0] == 'R') {
+            pos += rotations;
+        } else if (line[0] == 'L'){
+            pos -= rotations;
+        }
+
+        pos = @mod(pos, 100);
+
+        if (pos == 0) {
+            zero += 1;
+        }
+
+    } else |_| {
+    }
+
+    print("{d}\n", .{zero});
+}
+
+fn part2(reader: *std.Io.Reader) !void {
+    var pos: i32 = 50;
+    var zero: i32 = 0;
+    while (reader.takeDelimiterInclusive('\n')) |line| {
+        if (line.len == 0){
+            break;
+        }
+
+        const numSlice = std.mem.trimRight(u8, line[1..], &[_]u8{'\n'});
+        var rotations = try std.fmt.parseInt(i32, numSlice, 10);
+
+        zero += @divFloor(rotations, 100);
+        rotations = @rem(rotations, 100);
+        
+        if (line[0] == 'L'){
+            rotations *= -1;
+        }
+
+        const with_rotations: i32 = pos + rotations;
+        const new: i32 = @mod(with_rotations, 100);
+
+
+        if ((new != with_rotations and pos != 0) or new == 0){
+            zero += 1;
+        }
+
+        pos = new;
+
+
+    } else |_| {}
+
+    print("{d}\n", .{zero});
+}