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#include "common.h"
#include <map>
#include <vector>
namespace aoc2022 {
struct blizzard {
int x;
int y;
char c;
blizzard next(int height, int width) {
switch (c) {
case '>':
return {x + 1 == width - 1 ? 1 : x + 1, y, c};
case '<':
return {x - 1 == 0 ? width - 2 : x - 1, y, c};
case '^':
return {x, y - 1 == 0 ? height - 2 : y - 1, c};
case 'v':
return {x, y + 1 == height - 1 ? 1 : y + 1, c};
default:
break;
}
return *this;
}
friend bool operator<(blizzard b1, blizzard b2) { return b1.x < b2.x ? true : b1.x > b2.x ? false : b1.y < b2.y; }
friend bool operator==(blizzard b1, blizzard b2) { return b1.x == b2.x && b1.y == b2.y; }
};
struct valley {
int width;
int height;
char* pixel;
std::vector<std::vector<blizzard>> blzs;
valley(int w, int h) : width(w), height(h) {
pixel = (char*)malloc(width * height);
blzs.resize(1);
}
char& get(int h, int w) { return *(pixel + h * width + w); }
void load(int h, line_view lv) {
for (size_t i = 0; i < lv.length - 1; i++) {
char c = *(lv.line + i);
get(h, i) = c;
if (c == '<' || c == '>' || c == '^' || c == 'v') {
get(h, i) = '.';
blzs[0].emplace_back(blizzard{(int)i, h, c});
}
}
}
std::vector<blizzard> at(int t) {
t %= width * height;
while (blzs.size() < (size_t)t + 1) {
auto l = blzs.size() - 1;
std::vector<blizzard> n = blzs[l];
for (size_t i = 0; i < n.size(); i++) {
n[i] = n[i].next(height, width);
}
blzs.push_back(n);
}
return blzs[t];
}
void print(int t) {
std::map<blizzard, int> m;
auto blz = at(t);
for (auto& b : blz) {
auto p = m.insert({b, 1});
if (!p.second) {
p.first->second += 1;
}
}
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
auto it = m.find(blizzard{x, y, '.'});
if (it == m.end()) {
printf("%c", get(y, x));
} else {
if (it->second > 1) {
printf("%d", it->second);
} else {
printf("%c", it->first.c);
}
}
}
printf("\n");
}
}
};
std::pair<int, int> day24(line_view);
} // namespace aoc2022
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