Day 4

4/1-2.zig

@@ -0,0 +1,51 @@
+const std = @import("std");
+
+// I don't have much time for this, it ain't gonna
+// be as pretty as the other ones
+
+pub fn main() void {
+    var totalFit: usize = 0;
+    var totalAabb: usize = 0;
+
+    const input = @embedFile("input.asc");
+    var iter = std.mem.split(u8, input, "\n");
+
+    while(iter.next()) |line| {
+        if (line.len <= 0) continue;
+
+        //////////////////
+        // Split the nums into an array
+        ////////////////
+
+        const delim = "-,-";
+        if ((delim.len+1)&1 != 0) @panic("Amount of nums should always be even");
+        var nums = [_]u8{undefined} ** (delim.len+1);
+        var startIdx: usize = 0;
+
+        inline for(nums) |_,i| {
+            // Get the number
+            const numstr = if (i < delim.len)
+                std.mem.sliceTo(line[startIdx..], delim[i])
+            else
+                line[startIdx..];
+
+            startIdx += numstr.len + 1;
+            nums[i] = std.fmt.parseInt(u8, numstr, 10) catch unreachable;
+        }
+
+        if (fitTest(nums[0..2], nums[2..4])) totalFit += 1;
+        if (aabbTest(nums[0..2], nums[2..4])) totalAabb += 1;
+
+    }
+
+    std.debug.print("Part 1: {}\n", .{totalFit});
+    std.debug.print("Part 2: {}\n", .{totalAabb});
+}
+
+fn fitTest(a: []const u8, b: []const u8) bool {
+    return (a[0] >= b[0] and a[1] <= b[1]) or (b[0] >= a[0] and b[1] <= a[1]);
+}
+
+fn aabbTest(a: []const u8, b: []const u8) bool {
+    return a[1] >= b[0] and a[0] <= b[1];
+}