diff options
Diffstat (limited to '2020/20/solve.c')
| -rw-r--r-- | 2020/20/solve.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/2020/20/solve.c b/2020/20/solve.c new file mode 100644 index 0000000..15d0a64 --- /dev/null +++ b/2020/20/solve.c @@ -0,0 +1,191 @@ +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> + +#define COUNT 10 + +enum cnt_pos { T, R, B, L }; + +struct tile { + int id; + + int match[144]; + + int cnt[4]; // cnt_pos + int top[COUNT]; + int right[COUNT]; + int bottom[COUNT]; + int left[COUNT]; + int top_rev[COUNT]; + int right_rev[COUNT]; + int bottom_rev[COUNT]; + int left_rev[COUNT]; +}; + +void reverse(int dest[], int src[]) +{ + for (int i = 0; i < COUNT; i++) { + dest[COUNT - 1 - i] = src[i]; + } +} + +long part_one(FILE *fp) +{ + long res = 1; + + struct tile tiles[144] = { 0 }; + int tile_cnt = 0; + + char *line = NULL; + size_t len; + int y = 0; + while (getline(&line, &len, fp) != -1) { + int num; + if (line[0] == '\n') { + tile_cnt++; + } else if (sscanf(line, "Tile %d:", &num) == 1) { + struct tile new = { 0 }; + new.id = num; + tiles[tile_cnt] = new; + y = 0; + } else { + struct tile *tile = &tiles[tile_cnt]; + if (y == 0) { + for (int i = 0; i < COUNT; i++) { + tile->top[i] = line[i] == '#'; + tile->cnt[T] += tile->top[i]; + } + } else if (y == COUNT - 1) { + for (int i = 0; i < COUNT; i++) { + tile->bottom[i] = line[i] == '#'; + tile->cnt[B] += tile->bottom[i]; + } + } + tile->left[y] = line[0] == '#'; + tile->cnt[L] += tile->left[y]; + tile->right[y] = line[COUNT - 1] == '#'; + tile->cnt[R] += tile->right[y]; + y++; + } + } + tile_cnt++; + free(line); + + for (int i = 0; i < tile_cnt; i++) { + struct tile *tile = &tiles[i]; + reverse(tile->top_rev, tile->top); + } + + for (int i = 0; i < tile_cnt; i++) { + struct tile *tile = &tiles[i]; + // Find adjacent + int *cur, *cur_rev, cnt; + for (int j = 0; j < 4; j++) { // TRBL + switch (j) { + case T: + cnt = tile->cnt[T]; + cur = tile->top; + cur_rev = tile->top_rev; + break; + case R: + cnt = tile->cnt[R]; + cur = tile->right; + cur_rev = tile->right_rev; + break; + case B: + cnt = tile->cnt[B]; + cur = tile->bottom; + cur_rev = tile->bottom_rev; + break; + case L: + cnt = tile->cnt[L]; + cur = tile->left; + cur_rev = tile->left_rev; + break; + default: + exit(1); + break; + } + + for (int k = 0; k < tile_cnt; k++) { + printf("%d: %d %d\n", cnt, tile->id, j); + struct tile *cmp = &tiles[k]; + if (cmp->id == tile->id) + continue; + + int match_cnt = 0; + if (cnt == cmp->cnt[T]) { + if (!memcmp(cur, cmp->top, 40)) { + match_cnt++; + } else if (!memcmp(cur_rev, cmp->top, 40)) { + match_cnt++; + } + } + if (cnt == cmp->cnt[R]) { + if (!memcmp(cur, cmp->right, 40)) { + match_cnt++; + } else if (!memcmp(cur_rev, cmp->right, 40)) { + match_cnt++; + } + } + if (cnt == cmp->cnt[B]) { + if (!memcmp(cur, cmp->bottom, 40)) { + match_cnt++; + } else if (!memcmp(cur_rev, cmp->bottom, 40)) { + match_cnt++; + } + } + if (cnt == cmp->cnt[L]) { + if (!memcmp(cur, cmp->left, 40)) { + match_cnt++; + } else if (!memcmp(cur_rev, cmp->left, 40)) { + match_cnt++; + } + } + + tile->match[k] += match_cnt; + } + } + } + + for (int i = 0; i < tile_cnt; i++) { + struct tile *tile = &tiles[i]; + + int cnt = 0; + for (int j = 0; j < tile_cnt; j++) { + //if (tile->match[j] > cnt) + cnt += tile->match[j]; + } + + printf("%d - %d\n", cnt, tile->id); + /* res *= tile->id; */ + //printf("%d\n", tile->best_cnt); + } + + return res; +} + +long part_two(FILE *fp) +{ + long res = 0; + + return res; +} + +int main(int argc, char *argv[]) +{ + FILE *fp = fopen("input", "r"); + if (!fp) + exit(EXIT_FAILURE); + + clock_t tic = clock(); + printf("%lu\n", part_one(fp)); + rewind(fp); + printf("%lu\n", part_two(fp)); + clock_t toc = clock(); + printf("TIME: %f seconds\n", (double)(toc - tic) / CLOCKS_PER_SEC); + + fclose(fp); + return 0; +} |