Restructure repo and update solutions to zig 0.10.1HEADmaster

6 files changed, 633 insertions, 0 deletions

diff --git a/src/18/input b/src/18/input
new file mode 100644
index 0000000..2ceeee9
--- /dev/null
+++ b/src/18/input
@@ -0,0 +1,373 @@
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+6 + 3 + ((5 + 6 * 6 * 4 * 3 * 6) + 4) + 4 + (6 * 7 * 4 * 7 + 4 * 5) * 4
+3 * 2 + (4 * 4 * 3)
+9 + 7 + (8 + 4 * 5 * 7 + 3) * 9 * 6 + 4
+(3 * 8 + 9 + 8 + 5) + (2 * 6 * (2 * 4)) * 7 + (7 + 9 * (4 + 9 * 2 * 9 * 9) * 2) + (4 * 2 * 3 * 9)
+2 + 3 * 4 * 6 + 6
+8 * 4 * 8 + (2 * (5 + 9) * 3) * 6 * 4
+8 + (5 + 3 * 3) * 8 * (9 * 9 + 3 * (9 + 9 * 5 + 8 * 4 + 4) + 9) * ((5 * 7 * 7) * (9 + 6) * 6)
+2 + 5 + 7 + 8 * (4 + 9 * 4) + 7
+(7 + 9 + 7 + 2 * (5 + 3 * 6 * 5) * 4) + 5 + 8 * 3
+8 * 7 + (4 * 8 * 9 * 7 * 7 * 7) * 5 + 6 * 4
+((8 + 6 * 9 + 7 + 3) + (8 * 2 + 9 + 6) * 3 * 8 + 9 * 5) + (3 * 8 * 2 * 9 * 5) * 3 + (7 + (7 + 4 + 3) + 3) * (9 + 9 + 6 * 9 + 2 * 9)
+(9 * 3 + 2 + 5 * 9) * 5 + 6
+(3 * 6 + 5 * 9 + 2 * 6) + 2 * ((9 * 3) * 2 + (9 + 7) * 4 + (2 * 8 + 2 * 4 * 9) + 7) + 9 * (5 * (6 * 8 * 9) * 4 * 6 + 2) + 2
+2 + 9 + 6 + (6 + 6) * ((4 * 7 * 6 * 8 + 3 + 3) + 9 + 7) + ((2 * 2 * 6) + (9 + 2 + 6 + 2 + 8) + 4 * 7 * (7 + 4 + 4 * 5 + 8) * 4)
+7 * 4 + 9 + (5 + 9 + 9 + 4)
+2 * 8 * 2 + (4 * 9)
+7 * 3 + (5 + 8 * 4 * (9 + 6 * 8 + 2 * 3 + 9) + 2 * 9) * 9 * 5 + 9
+2 * (5 * 6 + 8 * 2 + 6) * 3 * 3 + 7
+(6 * 5) + 8 * 3 + 9 * (7 * 4 * (2 * 6 * 6 * 2)) + 6
+6 * 5 * 2 * 8 + 8 + (6 * 5 + (7 * 7) + 3 * (9 * 8 * 2 * 5 + 4 + 5))
+2 + 3 + 7 + (8 * 2 * 2)
+6 + 3 * ((9 + 7 * 4 + 4 * 3 * 6) + (3 * 5 + 8 + 3 * 3 + 4) * 5 + 5 * 5) * ((4 + 2) + 9 * 4 * 9 * 5)
+8 + 7 + 6 * 2 * ((8 * 3) * 3) * (2 + 5 * 5 + 5 * 8 + 8)
+5 * 2 * 8 * 4 * 7 * 2
+4 * 9 + 8 * ((9 * 5) + 5 * 2 * (6 * 4 + 2) * (2 + 8 * 8 + 8 * 2))
+3 * 2 + ((8 * 8) * 2 + 8 + 5 * 8 + 9) * ((4 * 7 * 4 + 5 + 6) * 6 * 3)
+(3 * (3 + 3) * 2 * 3 * (4 * 2 + 9 + 3 * 5 * 3)) * (2 * 2) * 3 + (5 * 5 * 6 + 2 + 2 * 3) + 7 * 2
+4 * (3 + 2)
+3 * 9 * 2 + (5 * 7 * 5 + 7 * 5 * 9) + 9
+2 + (5 * 7) + 3 + 7 * 8 * 8
+((4 * 6 * 8 + 4 + 4) * (2 + 3 + 5 * 2)) + (2 * 5) + 3
+9 + (5 * (3 + 8 * 7) + 8 + 4 + 8 * (6 * 2 * 7))
+9 + 6 + 6 * 3 * (2 + 7 + (5 + 7 + 4) + 3 * 2) + 5
+7 + (5 * 5 + (4 * 5 + 7 * 4 + 3 + 3) * 4 + 7)
+9 + 5 + 3 + ((7 + 7 + 2) + (6 + 9 + 7 + 4 * 5 + 7)) + 6 * 6
+5 * 8 * 2 + ((6 + 6 * 3 + 6 * 8 * 6) + 6 * 3) + 3 * 2
+(5 + 5 * 5 * (3 * 7 * 3 + 2) + 6 + 6) + 7 * 4 + (6 * (8 * 8 + 5) * 9 * 8 * 8 + 4) + 6
+(7 + 3 + 6 + 2 * 8 + 5) * 6 * (2 * (3 + 7 + 9 + 6) + 5 + 2) + 8
+((7 + 4) * 6 * 9) + 5
+2 * 7 + 5 + 4 + 7
+9 * (2 * 2 * 7 + 4 * (4 * 6 * 5 * 8))
+5 * 9 + 8
+6 * 2 * 8 + (5 + 3 + (8 + 9 + 6))
+3 * 5 + 9 * (4 + 2 + 9 + (5 * 3) * 3 + 6) * 5
+4 * 8 + (3 + 9 * 6) * 7 * (7 * 3 * 9 + 8 + 6 + (9 * 9 + 7 + 4)) + 8
+(2 * 9) * (6 * 8 * 6 + 5)
+9 * 2 * 3
+(6 + 2 * 9 + 5) * 6
+(8 + 3 + 2 * (2 + 8 * 2 + 6 * 2 + 2)) * 2
+(4 + 8 * 6) * 3 * 6 + 4 * (3 * 2 * 5 + 9 + 9) + 8
+3 + (9 * (8 + 6 + 8 * 7) * 8 * 7 + 7) * 7 + 8 + (2 + 3 + 6 * 6 + (2 + 4 + 6 + 5 * 3)) * 5
+((5 + 2) + (7 * 4 * 9 + 3) * (4 + 5 * 8 + 6 * 6) + (9 + 2) * 4) + 6 + 9 * 3 * 4 * 5
+2 + (7 * 5) + 4 + 3 + (3 * (7 + 2 * 6 * 7 + 6)) + 4
+2 + 6 + (3 + 2 + (2 + 3) + 7 * 4 * (8 * 7 * 2 * 4 + 8 * 5))
+4 * 3 + 6 + 5 * (9 + (2 * 4 * 8 * 8 + 8) + 2 + 4) + 9
+4 * 6 + (9 * 8 * 9 * 5 * 9 + 7) + 7
+(4 + (9 + 5 + 2 + 4 * 4 + 6) * 5 + 8) + (2 + 8 + (6 + 5 * 8 * 7) + (7 * 5)) + 5
+3 + 2 + (6 * 9 + 9 * 2) * (7 * (5 * 8) + 9 + 6 * (7 + 7 * 9 + 2 + 4) * 7) * 9
+5 + 9 * 7 * (8 * (6 + 4 * 5 + 3 * 2 * 4) + (5 + 2) * (6 * 3 * 7 * 6 + 8 + 3))
+5 * 7 * 2 + 7 * 6 + (2 * 7 + 5 * 5 * (6 + 7 + 5 + 7))
+4 + 7 * 2
+9 + ((6 * 7) + (9 + 7 + 7)) * 4
+5 + 6 * (3 * (8 * 8 * 3 + 4 * 5) + 4 + (2 + 7 + 3))
+(2 + 7 + 6) + 5 + 7 * 6 * 8 * 9
+2 * (6 + 9) * 8 * (9 + 4) + 7 + 8
+5 + 3 * 6 * 9 + (4 * 8 + 3 * 2)
+9 * (2 + 5 * 5) * 9 + (8 + 2 * (5 + 2 * 7 + 7 + 4 * 9) + 3 * 6 + 9) + 8
+8 + 4 + (2 + (9 * 2) * 5 * (5 * 8)) * 8 * 7
+5 * (3 * 5 + 6 * 4) + (7 * 5 * (6 + 6 * 7 * 8 * 6) + 8)
+5 + (4 * 6) + 6 * 5 + 6
+7 * 9 + ((6 + 3 + 6 * 4 * 4 * 6) + 7 + (6 + 4 * 7 * 3 + 9 * 6) + 4 + 9) + 6
+(8 * 6) + (3 * (3 + 2 * 7 * 9 + 9 + 9) * 3 + (2 + 8 * 5))
+3 * 4 * 6 * 4 * ((2 + 3 * 6) * 9)
+5 * ((8 * 5 + 7) + 4 + 7 + 6 * (9 * 6 * 3 + 9 * 7 + 2) + (4 + 4)) + 8 * (7 * (2 * 8 * 6) + 8 + 9 + 6) + 7
+2 * 8 * 5 * ((9 * 4 * 9 + 5 + 2) + (3 * 9) + (6 + 9 * 4 * 9 * 2) * 5 + 5) * 9
+5 + (7 * 8 + 7) + 2 * 5
+4 * (7 + 4 + 5 + (6 * 2 + 3)) * (7 * 3 * 7 * 8 * 7) * 2 * 2 + 2
+(4 + (5 + 5 * 8) + (5 * 5 + 3 * 5) + 6) + 6
+6 + (8 + 6 * 4 + 8 + (7 * 6) * 6) + 2 + 3
+(6 + 3) + ((8 * 7 * 6 * 6 + 6 * 7) * 4 * 6 * (3 + 3 * 2)) + 6
+4 * 2 * 3 * 3 * 7 + 9
+3 * 4 * 8 * (6 * 6 * 3 + (3 * 9 * 3 * 3 + 6)) + 5 + 4
+((7 * 2 + 7) + 9) * 2 * 8 * 3 + 3 * 3
+2 * 3 + ((2 * 5) + 8 * 7 * 5 + (8 * 2 * 4) * 8) * 3 + 7 * 8
+9 + (4 + 6) * 3
+(9 + 5) * 3 * 2 * 7 * (6 * 4 * 3)
+(3 * 3 * (3 * 3 * 5)) * 7 * 8 + (6 * 7 + 4) * 2 * 2
+(2 + 4 * (9 + 9 * 7 * 9) + 4) + 4 + 3
+(9 + 4 + 3) * 9 * 3 + 7 * 3
+6 + 4 + (6 + 2 + 4) + (9 + 7 * 8)
+7 + 9 + 5 * (3 + 9 * 7 + (5 + 8 + 9 * 4 + 6) * 5 * 8) + 9 * 6
+(3 * 7 * 7 * 3 + 7) + 4 * 3 + 5
+(8 + 7 * 2 + 5) * 4 + 7 * 2 + 5 + 3
+9 * 5 * ((5 * 8 + 2) * 7) + 2
+8 * 4 * 9 + 2
+4 + (3 + 5 * 7 * 3 * 8 + 5) * 6 + (3 + 2 + 9) * 5
+(3 * 5 + 8 * 8 * (7 * 6 + 2 * 6 + 9 * 7) * 9) * 7 * 9 + 9 + 3
+5 * 9 + 6
+6 * (8 + 3 + 4)
+2 + 5 + (4 + 5 + 8 * (8 + 6 * 9 * 8 + 3) * (3 + 9 * 3) + 3) + 7 + 2
+9 * (6 + 4) * 9 * 4 * 2 * ((4 + 3 + 2 * 9) + 6 + 5 + 8 * 7 + (7 * 7 + 6 + 2 + 8))
+(7 * 2 * (4 + 2 + 7 * 5 * 6 * 5) * (3 * 4 + 2) + 6) + 9 + 5 + 3
+4 * 5 * ((5 + 9 * 7 + 2) + 4 * 7 + 9) + 9 + 7
+7 * 2 * 6 + 9 + 5 * 6
+3 + 3 * 7 * ((3 * 3 + 2 + 7 * 5 + 2) + 7 * 6 * 2 * 5 * 9) + (4 * 5) + 7
+9 + ((5 + 5 * 7) + 7 * 2) + 7 + 6
+4 * 9 * 9 + ((9 + 3 + 7 * 4) * 4 + 2 + 9 + 8 + 6) * 6
+(6 * 2 * 5 + 4 + 5) + (8 + (8 * 5 + 7 * 7 + 6 * 2) * 6 + 6) + 4 * 8
+(5 + 6 * 2) * 5 * 6 * (5 * 5) + 9
+(7 + (9 * 4)) * ((4 + 3 + 5) + 7 * 5)
+2 * 5 + ((9 * 6 * 3 * 6 + 4) * 9 * 4) * 2 * 3 * (8 + 6)
+3 * 6 * 5 + 9 * (6 + 4 * 2 + 5 * 6)
+((7 + 8) + 3 + 7 + (8 * 3 * 6 + 8) * 2) * ((3 * 5 * 9) + 5) * 8 + 8
+((3 * 4 + 5 + 2) + 6 * 6) * 9
+4 + 6 * (9 * 6 * 7 + (2 * 5 + 5 * 9 + 6)) * 8
+4 * (2 + 2 + 9) + 5 + 5 * ((5 + 3) + 4 * 7)
+6 + 8 * 3 + 4
+2 + 8 + (8 + (7 + 5 * 3 * 8 * 7 + 2) * 6) + 3
diff --git a/src/18/input-test b/src/18/input-test
new file mode 100644
index 0000000..792bc09
--- /dev/null
+++ b/src/18/input-test
@@ -0,0 +1 @@
+1 + 2 * 3 + 4 * 5 + 6
diff --git a/src/18/input-test2 b/src/18/input-test2
new file mode 100644
index 0000000..ea858ad
--- /dev/null
+++ b/src/18/input-test2
@@ -0,0 +1 @@
+2 * 3 + (4 * 5)
diff --git a/src/18/main.zig b/src/18/main.zig
new file mode 100644
index 0000000..913a657
--- /dev/null
+++ b/src/18/main.zig
@@ -0,0 +1,177 @@
+// Own twist on https://en.wikipedia.org/wiki/Shunting-yard_algorithm
+
+const std = @import("std");
+const aoc = @import("aoc");
+
+const OpType = enum { ADD, MULT, COUNT };
+const Op = struct { prio: u32, optype: OpType };
+const Item = union(enum) { num: i64, op: OpType };
+
+const op_names = [_][]const u8{ "ADD", "MULT" };
+
+fn printStack(stack: []Item) void {
+    for (stack) |item| {
+        switch (item) {
+            .op => aoc.debugfmt("{s} ", .{op_names[@enumToInt(item.op)]}),
+            .num => aoc.debugfmt("{} ", .{item.num}),
+        }
+    }
+    aoc.debugfmt("\n", .{});
+}
+
+fn parseToken(line: []const u8, i: *usize, depth: *u32, op_prio: []const u32, mathstack: *std.ArrayList(Item), opstack: *std.ArrayList(Op)) !bool {
+    if (i.* > line.len) {
+        return false;
+    } else if (i.* == line.len) {
+        while (opstack.items.len > 0)
+            try mathstack.append(Item{ .op = opstack.pop().optype });
+    } else {
+        const c = line[i.*];
+        switch (c) {
+            '+', '*' => {
+                const optype = switch (c) {
+                    '+' => OpType.ADD,
+                    '*' => OpType.MULT,
+                    else => unreachable,
+                };
+                const prio = depth.* * @enumToInt(OpType.COUNT) + op_prio[@enumToInt(optype)];
+                while (opstack.items.len > 0 and
+                    opstack.items[opstack.items.len - 1].prio >= prio)
+                {
+                    try mathstack.append(Item{ .op = opstack.pop().optype });
+                }
+                try opstack.append(Op{ .optype = optype, .prio = prio });
+            },
+            '(' => depth.* += 1,
+            ')' => depth.* -= 1,
+            ' ' => {},
+            else => {
+                // in this case we know that every number is one digit..
+                // crappy zig parseInt requires span of exact int size
+                // before we even know the format >:(((
+                const val = try std.fmt.parseInt(i64, line[i.* .. i.* + 1], 10);
+                try mathstack.append(Item{ .num = val });
+            },
+        }
+    }
+    i.* += 1;
+    return true;
+}
+
+fn reduceStack(mathstack: *std.ArrayList(Item), opstack: *std.ArrayList(Op), tmpstack: *std.ArrayList(Item)) !void {
+    _ = opstack;
+
+    while (mathstack.items.len > 0) {
+        while (mathstack.items[mathstack.items.len - 1] != .op and
+            tmpstack.items.len > 0)
+        {
+            try mathstack.append(tmpstack.pop());
+        }
+        if (mathstack.items.len < 3 or mathstack.items[mathstack.items.len - 1] != .op)
+            break;
+        const op = mathstack.pop();
+
+        // get first arg
+        if (mathstack.items[mathstack.items.len - 1] != .num) {
+            try tmpstack.append(op);
+            continue;
+        }
+        const a = mathstack.pop();
+
+        // get second arg
+        if (mathstack.items[mathstack.items.len - 1] != .num) {
+            try tmpstack.append(op);
+            try tmpstack.append(a);
+            continue;
+        }
+        const b = mathstack.pop();
+
+        const result: i64 = switch (op.op) {
+            OpType.ADD => a.num + b.num,
+            OpType.MULT => a.num * b.num,
+            else => unreachable,
+        };
+        try mathstack.append(Item{ .num = result });
+    }
+}
+
+fn printRPN(allocator: std.mem.Allocator, input: []u8, prios: []const u32) !void {
+    var mathstack = std.ArrayList(Item).init(allocator);
+    defer mathstack.deinit();
+
+    var opstack = std.ArrayList(Op).init(allocator);
+    defer opstack.deinit();
+
+    var lineit = std.mem.tokenize(u8, input, "\n");
+    while (lineit.next()) |line| {
+        var depth: u32 = 0;
+        var i: usize = 0;
+        while (try parseToken(line, &i, &depth, prios, &mathstack, &opstack)) {}
+    }
+
+    printStack(mathstack.items);
+}
+
+fn partProto(allocator: std.mem.Allocator, input: []u8, prios: []const u32) !?[]u8 {
+    var answer: i64 = 0;
+
+    if (aoc.debug) {
+        aoc.debugfmt("Reverse Polish Notation:\n", .{});
+        try printRPN(allocator, input, prios);
+    }
+
+    var mathstack = std.ArrayList(Item).init(allocator);
+    defer mathstack.deinit();
+
+    var opstack = std.ArrayList(Op).init(allocator);
+    defer opstack.deinit();
+
+    var tmpstack = std.ArrayList(Item).init(allocator);
+    defer tmpstack.deinit();
+
+    var lineit = std.mem.tokenize(u8, input, "\n");
+    while (lineit.next()) |line| {
+        var depth: u32 = 0;
+        var i: usize = 0;
+        while (try parseToken(line, &i, &depth, prios, &mathstack, &opstack)) {
+            try reduceStack(&mathstack, &opstack, &tmpstack);
+        }
+
+        if (mathstack.items.len != 1) return aoc.Error.InvalidInput;
+        const last = mathstack.items[mathstack.items.len - 1];
+        if (last != .num) return aoc.Error.InvalidInput;
+        answer += last.num;
+
+        try mathstack.resize(0);
+        try opstack.resize(0);
+        try tmpstack.resize(0);
+    }
+
+    return try std.fmt.allocPrint(allocator, "{}", .{answer});
+}
+
+fn part1(allocator: std.mem.Allocator, input: []u8, args: [][]u8) !?[]u8 {
+    _ = args;
+
+    const prios = [_]u32{ 1, 1 };
+
+    return try partProto(allocator, input, prios[0..]);
+}
+
+fn part2(allocator: std.mem.Allocator, input: []u8, args: [][]u8) !?[]u8 {
+    _ = args;
+
+    const prios = [_]u32{ 2, 1 };
+
+    return try partProto(allocator, input, prios[0..]);
+}
+
+test "unions" {
+    const item1 = Item{ .op = OpType.MULT };
+    const item2 = Item{ .num = 1000 };
+    const expect = std.testing.expect;
+    expect(item1 == .op);
+    expect(item2 == .num);
+}
+
+pub const main = aoc.main(part1, part2, .{ "5783053349377", "74821486966872" });
diff --git a/src/18/part1 b/src/18/part1
new file mode 100644
index 0000000..7bff52b
--- /dev/null
+++ b/src/18/part1
@@ -0,0 +1,50 @@
+--- Day 18: Operation Order ---
+
+As you look out the window and notice a heavily-forested continent slowly appear over the horizon,
+you are interrupted by the child sitting next to you. They're curious if you could help them with
+their math homework.
+
+Unfortunately, it seems like this "math" follows different rules than you remember.
+
+The homework (your puzzle input) consists of a series of expressions that consist of addition (+),
+multiplication (*), and parentheses ((...)). Just like normal math, parentheses indicate that the
+expression inside must be evaluated before it can be used by the surrounding expression. Addition
+still finds the sum of the numbers on both sides of the operator, and multiplication still finds the
+product.
+
+However, the rules of operator precedence have changed. Rather than evaluating
+multiplication before addition, the operators have the same precedence, and are
+evaluated left-to-right regardless of the order in which they appear.
+
+For example, the steps to evaluate the expression 1 + 2 * 3 + 4 * 5 + 6 are as follows:
+
+1 + 2 * 3 + 4 * 5 + 6
+  3   * 3 + 4 * 5 + 6
+      9   + 4 * 5 + 6
+         13   * 5 + 6
+             65   + 6
+                 71
+
+Parentheses can override this order; for example, here is what happens if parentheses are added to
+form 1 + (2 * 3) + (4 * (5 + 6)):
+
+1 + (2 * 3) + (4 * (5 + 6))
+1 +    6    + (4 * (5 + 6))
+     7      + (4 * (5 + 6))
+     7      + (4 *   11   )
+     7      +     44
+            51
+
+Here are a few more examples:
+
+
+ - 2 * 3 + (4 * 5) becomes 26.
+ - 5 + (8 * 3 + 9 + 3 * 4 * 3) becomes 437.
+ - 5 * 9 * (7 * 3 * 3 + 9 * 3 + (8 + 6 * 4)) becomes 12240.
+ - ((2 + 4 * 9) * (6 + 9 * 8 + 6) + 6) + 2 + 4 * 2 becomes 13632.
+
+
+Before you can help with the homework, you need to understand it yourself. Evaluate the
+expression on each line of the homework; what is the sum of the resulting values?
+
+
diff --git a/src/18/part2 b/src/18/part2
new file mode 100644
index 0000000..4110043
--- /dev/null
+++ b/src/18/part2
@@ -0,0 +1,31 @@
+--- Part Two ---
+
+You manage to answer the child's questions and they finish part 1 of their homework, but get stuck
+when they reach the next section: advanced math.
+
+Now, addition and multiplication have different precedence levels, but they're not the
+ones you're familiar with. Instead, addition is evaluated before multiplication.
+
+For example, the steps to evaluate the expression 1 + 2 * 3 + 4 * 5 + 6 are now as follows:
+
+1 + 2 * 3 + 4 * 5 + 6
+  3   * 3 + 4 * 5 + 6
+  3   *   7   * 5 + 6
+  3   *   7   *  11
+     21       *  11
+         231
+
+Here are the other examples from above:
+
+
+ - 1 + (2 * 3) + (4 * (5 + 6)) still becomes 51.
+ - 2 * 3 + (4 * 5) becomes 46.
+ - 5 + (8 * 3 + 9 + 3 * 4 * 3) becomes 1445.
+ - 5 * 9 * (7 * 3 * 3 + 9 * 3 + (8 + 6 * 4)) becomes 669060.
+ - ((2 + 4 * 9) * (6 + 9 * 8 + 6) + 6) + 2 + 4 * 2 becomes 23340.
+
+
+What do you get if you add up the results of evaluating the homework problems using these
+new rules?
+
+