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#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
long add_or_mul(long *res, long num, int mul)
{
if (mul == 0)
*res += num;
else
*res *= num;
return *res;
}
long evil(char *str, int prec)
{
long res = 0;
int mul = 0, skip = 0, brace_cnt = 0;
for (char *p = str; *p; p++) {
if (skip) {
if (*p == '(') {
brace_cnt++;
} else if (*p == ')' && !(brace_cnt--)) {
brace_cnt = 0;
skip = 0;
}
continue;
}
if (*p == ' ') {
continue;
} else if (*p == '(') {
add_or_mul(&res, evil(p + 1, prec), mul);
skip = 1;
} else if (*p == ')') {
break; // That's why I don't use switch..case
} else if (*p == '*') {
if (prec)
return add_or_mul(&res, evil(p + 1, prec), 1);
mul = 1;
} else if (*p == '+') {
mul = 0;
} else if (isdigit(*p)) {
add_or_mul(&res, *p - '0', mul);
}
}
return res;
}
long part_one(FILE *fp)
{
long res = 0;
char *line = NULL;
size_t len;
while (getline(&line, &len, fp) != -1)
res += evil(line, 0);
return res;
}
long part_two(FILE *fp)
{
long res = 0;
char *line = NULL;
size_t len;
while (getline(&line, &len, fp) != -1)
res += evil(line, 1);
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;
}
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