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#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <malloc.h>
#include <string.h>
#include "../utils.h"
#define MAX_INPUT_LEN 128
void insert_value_sorted(int *list, size_t *size, int value)
{
long long low = 0, high = *size;
while (low < high) {
int m = low + (high - low) / 2;
if (list[m] < value) {
low = m + 1;
}
else if (list[m] > value) {
high = m;
}
else {
// Value already exists in the list
return;
}
}
for (long long i = *size - 1; i >= low; i--) {
list[i + 1] = list[i];
}
(*size)++;
list[low] = value;
}
uint64_t pos_seq(const int *input, size_t input_size)
{
// Use char to optimize for size
const static char TRIB[] = { 1, 1, 2, 4, 7 };
int con = 0;
uint64_t res = 1;
const int *prev = input;
const int *cur = input + 1;
do {
if (likely(*cur - *prev == 1)) {
con++;
}
else {
res *= TRIB[con];
con = 0;
}
} while (++prev && ++cur < input + input_size);
return res;
}
uint64_t solve(const char *filename)
{
FILE *file = fopen(filename, "r");
// Include space for newline and string terminator
char buffer[16] = { 0 };
int input[MAX_INPUT_LEN] = { 0 };
size_t input_size = 1; // 0 is our start value
while (fgets(buffer, 16, file)) {
insert_value_sorted(input, &input_size, atoi(buffer));
}
// Add our device's built-in joltage adapter
insert_value_sorted(input, &input_size, input[input_size - 1] + 3);
fclose(file);
return pos_seq(input, input_size);
}
int main(int argc, char *argv[])
{
printf("%lu\n", solve(argv[argc - 1]));
}
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