day 1

1 files changed, 55 insertions, 0 deletions

diff --git a/day-1/main_1.zig b/day-1/main_1.zig
new file mode 100644
index 0000000..1a36e26
--- /dev/null
+++ b/day-1/main_1.zig
@@ -0,0 +1,55 @@
+const std = @import("std");
+
+var gpa = std.heap.GeneralPurposeAllocator(.{}){};
+const allocator = gpa.allocator();
+
+pub fn main() !void {
+    var path_buffer: [std.fs.MAX_PATH_BYTES]u8 = undefined;
+    const path = try std.fs.realpath("./input", &path_buffer);
+
+    const file = try std.fs.openFileAbsolute(path, .{});
+    defer file.close();
+
+    const file_size = (try file.stat()).size;
+
+    const file_buffer = try file.readToEndAlloc(allocator, file_size);
+    defer allocator.free(file_buffer);
+
+    var iter = std.mem.split(u8, file_buffer, "\n");
+    var count: i32 = 0;
+    var max: [3]i32 = std.mem.zeroes([3]i32);
+
+    while (iter.next()) |line| {
+        if (line.len == 0) {
+            const lowest_u = lowest(i32, &max);
+            if (count > max[lowest_u]) {
+                max[lowest_u] = count;
+            }
+            count = 0;
+        } else {
+            count += try std.fmt.parseInt(i32, line, 0);
+        }
+    }
+
+    count = 0;
+    for (max) |v| {
+        count += v;
+    }
+
+    std.debug.print("{d}\n", .{count});
+}
+
+fn lowest(comptime T: type, items: []const T) usize {
+    var lowest_u: usize = 0;
+    var previous: T = items[0];
+
+    for (items) |item, idx| {
+        if (item < previous) {
+            lowest_u = idx;
+        }
+
+        previous = item;
+    }
+
+    return lowest_u;
+}