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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
struct rule {
int low1;
int high1;
int low2;
int high2;
};
int solve(FILE *fp)
{
// Part one
char *line = NULL;
size_t len = 0;
int paragraph = 0;
char name[64] = { 0 };
int ticket[64] = { 0 };
int valid[256][128] = { 0 };
int invalid[4096] = { 0 };
struct rule rules[64] = { 0 };
int rule_cnt = 0, invalid_cnt = 0, valid_cnt = 0;
while (getline(&line, &len, fp) != -1) {
if (line[0] == '\n') {
paragraph++;
continue;
}
if (paragraph == 0) {
int low1, high1, low2, high2;
sscanf(line, "%[^:]: %u-%u or %u-%u\n", name, &low1, &high1, &low2, &high2);
struct rule rule = {
.low1 = low1, .high1 = high1, .low2 = low2, .high2 = high2
};
rules[rule_cnt++] = rule;
} else if (paragraph == 1) {
if (line[0] == 'y')
continue;
int num, ind = 0;
int bytes_now, bytes_consumed = 0;
while (sscanf(line + bytes_consumed, "%d,%n", &num, &bytes_now) == 1) {
ticket[ind++] = num;
bytes_consumed += bytes_now;
}
} else if (paragraph == 2) {
if (line[0] == 'n')
continue;
int num;
int bytes_now, bytes_consumed = 0;
int valid_nums[128] = { 0 };
int invalid_ticket = 0, valid_nums_index = 0;
while (sscanf(line + bytes_consumed, "%d,%n", &num, &bytes_now) > 0) {
int inc = 0;
for (int i = 0; i < rule_cnt; i++) {
struct rule rule = rules[i];
if ((num >= rule.low1 && num <= rule.high1) ||
(num >= rule.low2 && num <= rule.high2)) {
inc = 0;
break;
} else {
inc = num;
}
}
if (inc) {
invalid[invalid_cnt++] = num;
invalid_ticket = 1;
}
if (!invalid_ticket)
valid_nums[valid_nums_index++] = num;
bytes_consumed += bytes_now;
}
if (!invalid_ticket)
memcpy(&valid[valid_cnt++], valid_nums,
valid_nums_index * sizeof(int));
}
}
int cnt = 0;
for (int i = 0; i < invalid_cnt; i++) {
cnt += invalid[i];
}
printf("%d\n", cnt);
// Part two
int used_rules[256] = { 0 };
int rule_used[64] = { 0 };
for (int x = 0; x < rule_cnt; x++) {
for (int j = 0; j < rule_cnt; j++) {
cnt = 0;
struct rule rule = rules[j];
for (int y = 0; y < valid_cnt; y++) {
int num = valid[y][x];
if ((num >= rule.low1 && num <= rule.high1) ||
(num >= rule.low2 && num <= rule.high2)) {
cnt++;
}
}
if (cnt == valid_cnt && !rule_used[j]) {
rule_used[j] = 1;
used_rules[x] = j;
break;
}
}
}
int res = 1;
for (int i = 0; i < rule_cnt; i++) {
if (used_rules[i] < 6)
res *= ticket[i];
}
return res;
}
int main(int argc, char *argv[])
{
FILE *fp = fopen("input", "r");
if (!fp)
exit(EXIT_FAILURE);
clock_t tic = clock();
printf("%d\n", solve(fp));
clock_t toc = clock();
printf("TIME: %f seconds\n", (double)(toc - tic) / CLOCKS_PER_SEC);
fclose(fp);
return 0;
}
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