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const std = @import("std");
const print = std.debug.print;
const assert = std.debug.assert;
const ArrayList = std.ArrayList;
const HashMap = std.HashMap;
const mem = std.mem;
const fin = mem.trim(u8, @embedFile("./input.txt"), &std.ascii.whitespace);
var gpa = std.heap.GeneralPurposeAllocator(.{}){};
const allocator = gpa.allocator();
fn evaluate(list: []const i64) struct { i64, i64 } {
if (mem.allEqual(i64, list, 0)) {
return .{ 0, 0 };
}
const n = list.len;
var derivative = ArrayList(i64).init(allocator);
defer derivative.deinit();
for (list[0 .. n - 1], list[1..n]) |curr, next| {
derivative.append(next - curr) catch unreachable;
}
const e = evaluate(derivative.items);
return .{ list[n - 1] + e, list[0] - e };
}
pub fn solve(listNums: ArrayList(ArrayList(i64))) void {
var part1: i64 = 0;
var part2: i64 = 0;
for (listNums.items) |list| {
const e = evaluate(list.items);
part1 += e[0];
part2 += e[1];
}
print("{d}\n{d}\n", .{ part1, part2 });
}
pub fn main() !void {
var splitLines = mem.splitScalar(u8, fin, '\n');
var listNums = ArrayList(ArrayList(i64)).init(allocator);
while (splitLines.next()) |line| {
var listText = mem.tokenizeScalar(u8, line, ' ');
var row = ArrayList(i64).init(allocator);
while (listText.next()) |n| {
try row.append(try std.fmt.parseInt(i64, n, 10));
}
try listNums.append(row);
}
solve(listNums);
}
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