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#include <stdlib.h>
#include <stdio.h>
#include <err.h>
#include <stdbool.h>
#include "input.h"
#define INPUT "input/04.txt"
#define EXPECTED1 51776L
#define EXPECTED2 16830L
#define BOARD_COUNT 100
#define BOARD_SIZE 5
#define MAX_DRAW 500
typedef struct {
long board[BOARD_SIZE][BOARD_SIZE];
bool board_marks[BOARD_SIZE][BOARD_SIZE];
} t_board;
bool board_is_winning(t_board* board) {
for(int i = 0; i < BOARD_SIZE; i++) {
bool winning_i = true;
bool winning_j = true;
for(int j = 0; j < BOARD_SIZE; j++) {
winning_i &= board->board_marks[i][j];
winning_j &= board->board_marks[j][i];
}
if(winning_i || winning_j)
return true;
}
return false;
}
bool board_mark(t_board* board, long draw) {
for(int i = 0; i < BOARD_SIZE; i++) {
for(int j = 0; j < BOARD_SIZE; j++) {
if(board->board[i][j] == draw)
board->board_marks[i][j] = true;
}
}
return board_is_winning(board);
}
void board_init(t_board* board) {
for(int i = 0; i < BOARD_SIZE; i++) {
for(int j = 0; j < BOARD_SIZE; j++) {
board->board[i][j] = 0;
board->board_marks[i][j] = false;
}
}
}
void board_read(t_board* board_list, struct input_str* input) {
for(int i = 0; i < BOARD_COUNT; i++) {
board_init(&(board_list[i]));
// read each line of the board
for(int j = 0; j < BOARD_SIZE; j++) {
// + 2 is for first line and empty line at start of board
int line_index = i * (BOARD_SIZE + 1) + j + 2;
char* line = input->lines[line_index];
char* start = line;
char* end = NULL;
// read each int
for(int k = 0; k < BOARD_SIZE; k++) {
board_list[i].board[j][k] = strtol(start, &end, 0);
start = end;
}
}
}
}
size_t draw_read(long* draw_list, struct input_str* input) {
size_t i = 0;
char *start = input->lines[0];
char *end = start;
while(i < MAX_DRAW && *end != '\n') {
draw_list[i] = strtol(start, &end, 0);
start = end + 1;
i++;
}
if(i == MAX_DRAW && *end != '\n')
err(1, "draw list was truncated");
return i;
}
long board_unmarked_sum(t_board* board) {
long sum = 0;
for(int i = 0; i < BOARD_SIZE; i++) {
for(int j = 0; j < BOARD_SIZE; j++) {
if(!(board->board_marks)[i][j])
sum += (board->board)[i][j];
}
}
return sum;
}
void part1(struct input_str* input) {
t_board board_list[BOARD_COUNT];
long draw_list[MAX_DRAW];
board_read(board_list, input);
size_t draw_count = draw_read(draw_list, input);
// apply draw to each board until one is winning
for(size_t i = 0; i < draw_count; i++) {
for(size_t j = 0; j < BOARD_COUNT; j++) {
if(board_mark(&(board_list[j]), draw_list[i])) {
// winning board found, print score
long score = board_unmarked_sum(&(board_list[j]));
CHECK(draw_list[i] * score, EXPECTED1)
return;
}
}
}
err(1, "no winning board");
}
void part2(struct input_str* input) {
t_board board_list[BOARD_COUNT];
long draw_list[MAX_DRAW];
board_read(board_list, input);
size_t draw_count = draw_read(draw_list, input);
// apply draw to each board until one is winning
long last_score;
for(size_t i = 0; i < draw_count; i++) {
for(size_t j = 0; j < BOARD_COUNT; j++) {
// skip already winning boards
if(board_is_winning(&(board_list[j])))
continue;
if(board_mark(&(board_list[j]), draw_list[i])) {
// winning board found
last_score = draw_list[i] * board_unmarked_sum(&(board_list[j]));
}
}
}
// print last winning
CHECK(last_score, EXPECTED2)
}
int main() {
// read input
struct input_str input;
input_str_read(&input, INPUT);
// do stuff
part1(&input);
part2(&input);
// cleanup & exit
input_str_free(&input);
return 0;
}
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