Day 3... what was thatttt

AdventOfCode2023/src/day3/day3.zig

@@ -0,0 +1,174 @@
+const std = @import("std");
+
+pub fn solve(input: [][]const u8) !void {
+    const a = std.heap.page_allocator;
+    var arena = std.heap.ArenaAllocator.init(a);
+    var allocator = arena.allocator();
+    defer arena.deinit();
+
+    // Grid of usize
+    var grid = try allocator.alloc([]i32, input.len);
+
+    for (0..grid.len) |index| {
+        grid[index] = try allocator.alloc(i32, input[0].len);
+    }
+
+    var currentNumber: u32 = 0;
+    for (0..grid.len) |i| {
+        if (currentNumber != 0) {
+            var digitCount = std.math.log10(currentNumber) + 1;
+
+            for (0..digitCount) |k| {
+                var typedCurrentNum: i32 = @intCast(currentNumber);
+                grid[i - 1][grid[0].len - 1 - k] = typedCurrentNum;
+            }
+            currentNumber = 0;
+        }
+
+        for (0..grid[0].len) |j| {
+            var char = input[i][j];
+            if (char >= '0' and char <= '9') {
+                currentNumber *= 10;
+                currentNumber += char - '0';
+            } else if (j > 0 and currentNumber > 0) {
+                // How many digits did you span
+                var digitCount = std.math.log10(currentNumber) + 1;
+
+                for (0..digitCount) |k| {
+                    var typedCurrentNum: i32 = @intCast(currentNumber);
+                    grid[i][j - 1 - k] = typedCurrentNum;
+                }
+                currentNumber = 0;
+
+                if (input[i][j] == '.') {
+                    grid[i][j] = 0;
+                } else if (input[i][j] == '*') {
+                    grid[i][j] = -2; // gear
+                } else {
+                    grid[i][j] = -1; // any symbol
+                }
+            } else {
+                if (input[i][j] == '.') {
+                    grid[i][j] = 0;
+                } else if (input[i][j] == '*') {
+                    grid[i][j] = -2; // gear
+                } else {
+                    grid[i][j] = -1; // any symbol
+                }
+            }
+        }
+    }
+
+    if (currentNumber != 0) {
+        var digitCount = std.math.log10(currentNumber) + 1;
+        for (0..digitCount) |k| {
+            var typedCurrentNum: i32 = @intCast(currentNumber);
+            grid[grid.len - 1][grid[0].len - k - 1] = typedCurrentNum;
+        }
+        currentNumber = 0;
+    }
+
+    // for (0..grid.len) |i| {
+    //     for (0..grid[0].len) |j| {
+    //         std.debug.print("{}, ", .{grid[i][j]});
+    //     }
+    //     std.debug.print("\n", .{});
+    // }
+
+    var part1: i32 = 0;
+    var lastAddedNumber: i32 = 0;
+
+    for (0..grid.len) |i| {
+        for (0..grid[0].len) |j| {
+            if (grid[i][j] > 0) {
+                // std.debug.print("Num: {}\n", .{grid[i][j]});
+                for (0..3) |aroundI| {
+                    if (aroundI == 0 and i == 0) {
+                        continue;
+                    }
+
+                    if (aroundI == 2 and i == grid.len - 1) {
+                        continue;
+                    }
+
+                    // std.debug.print("Checking aroudnI: {}\n", .{aroundI});
+                    for (0..3) |aroundJ| {
+                        if (aroundI == 1 and aroundJ == 1) {
+                            continue;
+                        }
+                        if (aroundJ == 0 and j == 0) {
+                            continue;
+                        }
+                        if (aroundJ == 2 and j == grid[0].len - 1) {
+                            continue;
+                        }
+
+                        // std.debug.print("checking {},{}\n", .{ aroundI, aroundJ });
+                        if (grid[i + aroundI - 1][j + aroundJ - 1] <= -1) {
+                            if (lastAddedNumber != grid[i][j]) {
+                                lastAddedNumber = grid[i][j];
+                                part1 += lastAddedNumber;
+                            }
+                        }
+                    }
+                }
+            } else {
+                lastAddedNumber = 0;
+            }
+        }
+    }
+
+    var part2: i32 = 0;
+
+    for (0..grid.len) |i| {
+        for (0..grid[0].len) |j| {
+            if (grid[i][j] == -2) {
+                var product: i32 = 1;
+                var numOfnums: usize = 0;
+                // std.debug.print("Num: {}\n", .{grid[i][j]});
+                for (0..3) |aroundI| {
+                    var prevGear: i32 = 0;
+                    if (aroundI == 0 and i == 0) {
+                        continue;
+                    }
+
+                    if (aroundI == 2 and i == grid.len - 1) {
+                        continue;
+                    }
+
+                    // std.debug.print("Checking aroudnI: {}\n", .{aroundI});
+                    for (0..3) |aroundJ| {
+                        if (aroundI == 1 and aroundJ == 1) {
+                            continue;
+                        }
+                        if (aroundJ == 0 and j == 0) {
+                            continue;
+                        }
+                        if (aroundJ == 2 and j == grid[0].len - 1) {
+                            continue;
+                        }
+
+                        // std.debug.print("checking {},{}\n", .{ aroundI, aroundJ });
+                        if (grid[i + aroundI - 1][j + aroundJ - 1] > 0) {
+                            if (prevGear == grid[i + aroundI - 1][j + aroundJ - 1]) {
+                                continue;
+                            }
+                            prevGear = grid[i + aroundI - 1][j + aroundJ - 1];
+                            // Found number
+                            product *= grid[i + aroundI - 1][j + aroundJ - 1];
+                            numOfnums += 1;
+                        } else {
+                            prevGear = 0;
+                        }
+                    }
+                }
+                if (numOfnums == 2) {
+                    part2 += product;
+                }
+            }
+        }
+    }
+
+    std.debug.print("Part1: {}\n", .{part1});
+    std.debug.print("Part2: {}\n", .{part2});
+}

AdventOfCode2023/src/main.zig

@@ -1,12 +1,13 @@
 const std = @import("std");
 // const day1 = @import("./day1/day1.zig");
-const day2 = @import("./day2/day2.zig");
+// const day2 = @import("./day2/day2.zig");
+const day3 = @import("./day3/day3.zig");
 const utils = @import("utils.zig");
 
 pub fn main() !void {
     const allocator = std.heap.page_allocator;
-    var input = try utils.getInput("./src/day2/input.txt", allocator);
+    var input = try utils.getInput("./src/day3/input.txt", allocator);
     defer allocator.free(input);
 
-    try day2.solve(input);
+    try day3.solve(input);
 }