From 9e515bfd50e08058ad8c27f2878582d304f0251d Mon Sep 17 00:00:00 2001
From: Jeremy Kaplan <code@jdkaplan.dev>
Date: Fri, 6 Dec 2024 23:23:20 -0800
Subject: [PATCH] 2024: try parseAll

---
 2024/src/aoc.zig   | 17 +++++++++++++++++
 2024/src/day07.zig | 28 +++++-----------------------
 2 files changed, 22 insertions(+), 23 deletions(-)

diff --git a/2024/src/aoc.zig b/2024/src/aoc.zig
index df1bb5d..57d4388 100644
--- a/2024/src/aoc.zig
+++ b/2024/src/aoc.zig
@@ -65,3 +65,20 @@ pub fn AutoHashSet(comptime T: type) type {
         }
     };
 }
+
+pub fn parseAll(
+    comptime T: type,
+    allocator: std.mem.Allocator,
+    text: []const u8,
+    sep: []const u8,
+) !std.ArrayList(T) {
+    var all = std.ArrayList(T).init(allocator);
+
+    var it = std.mem.tokenizeSequence(u8, text, sep);
+    while (it.next()) |s| {
+        const eqn = try T.parse(allocator, s);
+        try all.append(eqn);
+    }
+
+    return all;
+}
diff --git a/2024/src/day07.zig b/2024/src/day07.zig
index 1b3319e..7c3c01d 100644
--- a/2024/src/day07.zig
+++ b/2024/src/day07.zig
@@ -15,7 +15,7 @@ pub fn main() !void {
     const text = try file.readToEndAlloc(allocator, comptime 1 << 30);
     defer allocator.free(text);
 
-    var equations = try Equation.parseAll(allocator, text);
+    var equations = try aoc.parseAll(Equation, allocator, text, "\n");
     defer equations.deinit();
     defer {
         for (equations.items) |*eqn| eqn.deinit();
@@ -45,7 +45,9 @@ fn part1(allocator: Allocator, equations: []Equation) !u64 {
 fn part2(allocator: Allocator, equations: []Equation) !u64 {
     var sum: u64 = 0;
     for (equations) |eqn| {
-        if (try eqn.solvable(allocator, &[_]Operator{ .Plus, .Times }) or try eqn.solvable(allocator, &[_]Operator{ .Plus, .Times, .Concat })) {
+        const ops1 = &[_]Operator{ .Plus, .Times };
+        const ops2 = &[_]Operator{ .Plus, .Times, .Concat };
+        if (try eqn.solvable(allocator, ops1) or try eqn.solvable(allocator, ops2)) {
             sum += eqn.value;
         }
     }
@@ -95,7 +97,7 @@ const Equation = struct {
         self.operands.deinit();
     }
 
-    fn parse(allocator: Allocator, line: []const u8) !Self {
+    pub fn parse(allocator: Allocator, line: []const u8) !Self {
         const value, const rest = a: {
             var it = std.mem.splitSequence(u8, line, ": ");
             const value = try std.fmt.parseInt(u64, it.next().?, 10);
@@ -115,26 +117,6 @@ const Equation = struct {
         return .{ .value = value, .operands = operands };
     }
 
-    fn parseAll(allocator: Allocator, text: []const u8) !ArrayList(Self) {
-        var all = ArrayList(Self).init(allocator);
-
-        var it = std.mem.tokenizeScalar(u8, text, '\n');
-        while (it.next()) |line| {
-            const eqn = try Self.parse(allocator, line);
-            try all.append(eqn);
-        }
-
-        return all;
-    }
-
-    fn eval(self: Self, operators: ArrayList(Operator)) u64 {
-        var v = self.operands.items[0];
-        for (self.operands.items[1 .. operators.items.len + 1], operators.items) |n, op| {
-            v = op.eval(v, n);
-        }
-        return v;
-    }
-
     fn solvable(self: Self, allocator: Allocator, operators: []const Operator) !bool {
         const State = struct {
             partial: u64,