aoc

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git clone https://codeberg.org/night0721/aoc
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1.c (3160B)

      1 #include <stdio.h>
      2 #include <string.h>
      3 #include <stdlib.h>
      4 #include <ctype.h>
      5 #include <stdbool.h>
      6 
      7 int main() {
      8     int LINE_LENGTH = 140;
      9     FILE *inputfile = fopen("./input", "r");
     10     char line[2048] = { 0 };
     11     size_t len = 0;
     12     ssize_t read;
     13     if (inputfile == NULL) {
     14         printf("Input file not found. Exiting.");
     15         exit(1);
     16     }
     17     char **lines = malloc(sizeof(char *) * LINE_LENGTH);
     18     int line_count = 0;
     19     while (fgets(line, 1024, inputfile)) {
     20         lines[line_count] = malloc(sizeof(char) * 2048);
     21         strcpy(lines[line_count], line);
     22         line_count++;
     23     }
     24     int *goodnumbers = malloc(sizeof(int) * 4096);
     25     int goodnumber_count = 0;
     26     for (int i = 0; i < LINE_LENGTH; i++) {
     27         char *line = lines[i];
     28         for (int j = 0; j < strlen(lines[i]); j++) {
     29             bool append = false;
     30             char *number = malloc(sizeof(char) * 2048);
     31             while (isdigit(*(line + j)) != 0) {
     32                 number[strlen(number)] = line[j];
     33                 // check left and right is symbol or not
     34                 int prev = j - 1;
     35                 int next = j + 1;
     36                 if (prev > 0) {
     37                     if (line[prev] != '.' && isdigit(line[prev]) == 0) {
     38                         // append to good numbers
     39                         append = true;
     40                     }
     41                     // check if on first line, as we can't go back further then check is previous line previous char is symbol or not
     42                     if (i != 0 && lines[i - 1][prev] != '.' && isdigit(lines[i - 1][prev]) == 0) {
     43                         append = true;
     44                     }
     45                     // check if next line exists
     46                     if (i != LINE_LENGTH - 1 && lines[i + 1][prev] != '.' && isdigit(lines[i + 1][prev]) == 0) {
     47                         append = true;
     48                     }
     49                 }
     50                 if (next <= strlen(line) - 1) {
     51                     if (line[next] != '.' && line[next] != '\n' && isdigit(line[next]) == 0) {
     52                         append = true;
     53                     }
     54 
     55                     if (i != 0 && lines[i - 1][next] != '.' && lines[i - 1][next] != '\n' && isdigit(lines[i - 1][next]) == 0) {
     56                         append = true;
     57                     }
     58                     if (i != LINE_LENGTH - 1 && lines[i + 1][next] != '.' && lines[i + 1][next] != '\n' && isdigit(lines[i + 1][next]) == 0) {
     59                         append = true;
     60                     }
     61                 }
     62                 if (i != 0 && lines[i - 1][j] != '.' && isdigit(lines[i - 1][j]) == 0) {
     63                     append = true;
     64                 }
     65                 if (i != LINE_LENGTH - 1 && lines[i + 1][j] != '.' && isdigit(lines[i + 1][j]) == 0) {
     66                     append = true;
     67                 }
     68                 j++;
     69             }
     70             if (append) {
     71                 goodnumbers[goodnumber_count] = atoi(number);
     72                 goodnumber_count++;
     73                 append = false;
     74             }
     75             
     76         }
     77     }
     78     int sum = 0;
     79     for (int i = 0; i < goodnumber_count; i++) {
     80         sum += goodnumbers[i];
     81     }
     82     printf("Sum: %d\n", sum);
     83 }