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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <assert.h>
#include "vec.h"
#include "str.h"
#include "map.h"
void* read_input() {
FILE* fp = fopen("./input", "r");
void *vec = new_vec();
while(1) {
char *line = fgetline(fp);
if (line == NULL) break;
char *stripped = str_strip(line);
if (strlen(stripped) == 0) break;
vec_push_back(vec, stripped);
}
return vec;
}
typedef struct {
int line;
int column;
int value;
int length;
} num_t;
char *compose_key(int x, int y) {
void* ss = new_ss();
ss_add(ss, "%d,%d", x, y);
return ss_cstr(ss);
}
void *parse_nums(void *schema) {
void *nums = new_vec();
int j = 0;
const int IN_NUM = 0, IDLE = 1;
int state = IDLE;
for (int i = 0; i < vec_size(schema); i++) {
char *line = vec_get(schema, i);
int line_len = strlen(line);
int value = 0;
int length = 0;
state = IDLE;
j = 0;
while (1) {
char c = '.';
if (j < line_len) c = line[j];
if (state == IDLE) {
if (isdigit(c)) {
state = IN_NUM;
continue;
} else {
j++;
if (j >= line_len) break;
continue;
}
} else if (state == IN_NUM) {
if (isdigit(c)) {
value = value * 10 + (c - '0');
length++;
j++;
continue;
} else {
num_t *n = malloc(sizeof(num_t));
*n = (num_t){
.line = i,
.column = j - length,
.value = value,
.length = length
};
vec_push_back(nums, n);
value = 0;
length = 0;
state = IDLE;
if (j >= line_len) break;
continue;
}
}
}
}
return nums;
}
char char_at(void *schema, int line, int column) {
char *buf = vec_get(schema, line);
return buf[column];
}
void mark_asterisks(void *asterisks, num_t *num, int x, int y) {
const char *key = compose_key(x, y);
void *num_list = dict_get(asterisks, key);
if (num_list == NULL) {
num_list = new_vec();
dict_set(asterisks, key, num_list);
}
vec_push_back(num_list, num);
}
void find_asterisks(void *schema, void *asterisks, num_t *num) {
int line_len = vec_size(schema);
int col_len = strlen(vec_get(schema, 0));
for (int i = num->column - 1; i < num->column + num->length + 1; i++) {
if (num->line - 1 < 0) continue;
if (i < 0 || i >= col_len) continue;
char c = char_at(schema, num->line - 1, i);
if (c == '*') mark_asterisks(asterisks, num, num->line - 1, i);
}
for (int i = num->column - 1; i < num->column + num->length + 1; i++) {
if (num->line + 1 >= line_len) continue;
if (i < 0 || i >= col_len) continue;
char c = char_at(schema, num->line + 1, i);
if (c == '*') mark_asterisks(asterisks, num, num->line + 1, i);
}
if (num->column - 1 >= 0) {
char c = char_at(schema, num->line, num->column - 1);
if (c == '*') mark_asterisks(asterisks, num, num->line, num->column - 1);
}
if (num->column + num->length < col_len) {
char c = char_at(schema, num->line, num->column + num->length);
if (c == '*') mark_asterisks(asterisks, num, num->line, num->column + num->length);
}
}
int main() {
void *schema = read_input();
void *nums = parse_nums(schema);
int sum = 0;
void *asterisks = new_dict();
for (int i = 0; i < vec_size(nums); i++) {
num_t *num = vec_get(nums, i);
find_asterisks(schema, asterisks, num);
}
for (void *iter = dict_begin(asterisks);
iter != NULL;
iter = dict_next(asterisks, iter)) {
void *list = dict_iter_value(iter);
if (vec_size(list) == 2) {
num_t* n1 = vec_get(list, 0);
num_t* n2 = vec_get(list, 1);
sum += n1->value * n2->value;
}
}
printf("%d\n", sum);
return 0;
}
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