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const std = @import("std");
const day3 = @import("day3");
// test "is invalid" {
// try std.testing.expect(isInvalid("11", 1) == true);
// }
fn getCurrentIndex(arr: [12]u8) usize {
for (arr, 0..) |v, i| {
if (v == '0') {
return i;
}
}
return 12;
}
fn isArr1Bigger(arr1: [12]u8, arr2: [12]u8) bool {
for (arr1, arr2) |a1, a2| {
if (a1 > a2) {
return true;
} else if (a1 == a2) {
continue;
} else if (a1 < a2) {
return false;
}
}
return true; // they are the same
}
fn addJoltage(arr: [12]u8) u64 {
var result: u64 = 0;
for (arr, 0..) |v, i| {
result += (v - '0') * std.math.pow(u64, 10, 12 - i - 1);
}
return result;
}
pub fn main() !void {
// Initiate allocator
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
defer _ = gpa.deinit();
const alloc = gpa.allocator();
// Read contents from file "./filename"
const cwd = std.fs.cwd();
const fileContents = try cwd.readFileAlloc(alloc, "day3.txt", 24000);
defer alloc.free(fileContents);
// Print file contents
// std.debug.print("{s}", .{fileContents});
var splits = std.mem.splitScalar(u8, fileContents, '\n');
var joltage: u64 = 0;
while (splits.next()) |bank| {
if (bank.len < 1) {
continue;
}
var stack = std.array_list.Aligned([12]u8, null).empty;
var managed_stack = stack.toManaged(alloc);
defer managed_stack.deinit();
var current_largest: [12]u8 = .{'0'} ** 12;
try managed_stack.append(current_largest);
for (bank[0..]) |battery| {
const l = managed_stack.items.len;
for (0..l) |current_index| {
const current_value = managed_stack.items[current_index];
const c_ind = getCurrentIndex(current_value);
if (c_ind == 12) {
continue;
}
var new_curr: [12]u8 = current_value;
new_curr[c_ind] = battery;
if (isArr1Bigger(new_curr, current_largest)) {
// std.debug.print("bank: {s} current {s}, current_index: {d} current_largest: {s}\n", .{ bank, current_value, c_ind, current_largest });
if (c_ind == 11) {
current_largest = new_curr;
}
try managed_stack.append(new_curr);
}
}
}
for (managed_stack.items) |current_value| {
const c_ind = getCurrentIndex(current_value);
if (c_ind == 12) {
// std.debug.print("current {s}, current_index{d}\n", .{ current_value, c_ind });
if (isArr1Bigger(current_value, current_largest)) {
current_largest = current_value;
}
}
}
std.debug.print("\ncurrent largest {s}\n", .{current_largest});
joltage += addJoltage(current_largest);
std.debug.print("joltage running total {}\n\n", .{joltage});
}
std.debug.print("joltage: {}\n", .{joltage});
try day3.bufferedPrint();
}
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