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#include "aoc.h"
#include <algorithm>
namespace aoc2019 {
struct digits {
int chars[10] = {0};
};
struct layer {
char ds[25 * 6] = {0};
};
//static void print(layer * l){
// for(size_t i = 0; i < ARRAY_SIZE(l->ds); i++) {
// printf("%s", l->ds[i] > 0 ? "#" : ".");
// if ((i + 1) % 25 == 0) {
// printf("\n");
// }
// }
//}
static void fold_layers(const char* p1, const char* p2, digits* p, layer* l) {
int index{0};
auto reset = [](char x, char y) { return y == 0 || y == 1 ? y : x; };
while (p1 < p2) {
p->chars[*p1 - '0'] += 1;
l->ds[index] = reset(*p1 - '0', l->ds[index]);
p1++;
index++;
}
}
std::pair<int, int> day8(line_view file) {
digits ds[100];
int x = 6 * 25;
layer top;
memset(&top.ds, 2, sizeof(layer));
for (int i = 0; i < 100; i++) {
const char* p1 = file.line + i * x;
const char* p2 = file.line + (i + 1) * x;
fold_layers(p1, p2, &ds[i], &top);
}
struct ct {
int zeros = 0;
int times = 0;
} cs[100];
for (int i = 0; i < 100; i++) {
cs[i].zeros = ds[i].chars[0];
cs[i].times = ds[i].chars[1] * ds[i].chars[2];
}
std::sort(cs, cs + 100, [](ct c1, ct c2) { return c1.zeros < c2.zeros; });
// print(&top);
return {cs[0].times, 0};
}
} // namespace aoc2019
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