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#pragma once
#include "common.h"
#include <unordered_map>
#include <vector>
namespace aoc2020 {
struct color_bag {
line_view color;
std::vector<std::pair<color_bag*, int>> bags;
};
struct bag_regulations {
std::unordered_map<line_view, color_bag*> regulations;
void get_number(const char** pp, int* d) {
const char* p = *pp;
*d = 0;
while (*p >= '0' && *p <= '9') {
*d = *d * 10 + *p - '0';
p++;
}
*pp = p;
}
std::pair<color_bag*, int> get_bag(const char* p1, const char* p2) {
int d{0};
get_number(&p1, &d);
line_view color = {d > 0 ? p1 + 1 : p1, *(p2 - 1) == 's' ? p2 - 5 : p2 - 4};
color_bag* bag = nullptr;
auto it = regulations.find(color);
if (it == regulations.end()) {
bag = new color_bag{color, {}};
regulations.insert({color, bag});
} else {
bag = it->second;
}
return {bag, d};
}
void parse(line_view lv) {
const char* p1 = lv.line;
const char* p2 = lv.line + lv.length;
const char* p = lv.contains("contain");
auto pa1 = get_bag(p1, p - 1);
p1 = p + 8;
p = p1;
while (p < p2) {
if (*p == ',' || *p == '.') {
pa1.first->bags.push_back(get_bag(p1, p));
p1 = p + 2;
}
p++;
}
}
};
std::pair<int, int> day7(line_view, const char*);
} // namespace aoc2020
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