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const std = @import("std");
const print = std.debug.print;
pub fn solve(part: []u8, reader: *std.Io.Reader, allocator: std.mem.Allocator) !void {
if (std.mem.eql(u8, part, "1")) {
try part1(reader, allocator);
} else {
try part2(reader, allocator);
}
}
fn part1(reader: *std.Io.Reader, allocator: std.mem.Allocator) !void {
var output: usize = 0;
const first = try reader.takeDelimiter('\n');
var space = try allocator.alloc(bool, first.?.len);
defer allocator.free(space);
for (space) |*b| b.* = false;
space[(first.?.len - 1) / 2] = true;
while (reader.takeDelimiter('\n')) |line| {
if (line == null) {
break;
}
for (line.?,0..) |e, i| {
if (e == '^' and space[i]) {
space[i] = false;
space[i-1] = true;
space[i+1] = true;
output += 1;
}
}
} else |_| {}
print("{d}\n", .{output});
}
fn quantum(space: [][]u8, pos: usize, y: usize, output: *usize) void {
if (space.len == y){
return;
}
if (space[y][pos] == '^') {
quantum(space, pos - 1, y + 1, output);
output.* += 1;
quantum(space, pos + 1, y + 1, output);
} else {
quantum(space, pos, y + 1, output);
}
}
fn part2(reader: *std.Io.Reader, allocator: std.mem.Allocator) !void {
var output: usize = 1;
const first = try reader.takeDelimiter('\n');
var space = try allocator.alloc(usize, first.?.len);
defer allocator.free(space);
for (space) |*b| b.* = 0;
space[(first.?.len - 1) / 2] = 1;
while (reader.takeDelimiter('\n')) |line| {
if (line == null) {
break;
}
for (line.?,0..) |e, i| {
if (e == '^' and space[i] > 0) {
space[i-1] += space[i];
space[i+1] += space[i];
output += space[i];
space[i] = 0;
}
}
} else |_| {}
print("{d}\n", .{output});
}
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