feat(01): Solved part 1

01/src/main.c

@@ -5,21 +5,71 @@
  * @brief Main entry point
  * @author jiriks74
  */
-
+#define _GNU_SOURCE
+// #define _LINE_LEN (size_t *)100
+#define _LINE_LEN 100
 #include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/**
+ * @brief Gets a calibration value from a line
+ * @param char* line containing the calibration value
+ * @return int the calibration value
+ */
+int getVal(char *str) {
+  int num = 0;
+  int lastNum = -1;
+  for (int i = 0; i < strlen(str); i++) {
+    if (str[i] >= *"0" && str[i] <= *"9") {
+      if (num == 0) {
+        num = (str[i] - 48) * 10;
+      } else {
+        lastNum = str[i] - 48;
+      }
+    }
+  }
+  if (lastNum == -1) {
+    num += num / 10;
+  } else {
+    num += lastNum;
+  }
+  return num;
+}
 
 /**
  * @brief Main entry point
  * @param argc Number of command-line arguments.
  * @param argv Array of command-line arguments.
  */
-#ifndef TESTING
+#ifdef TESTING
+int mainTest(FILE *stdin, int argc, char *argv[])
+#else
 int main(int argc, char *argv[])
 #endif
-#ifdef TESTING
-    int main_test(int argc, char *argv[])
-#endif
 {
-  printf("Hello world!\n");
-  return 0;
+  FILE *file;
+  if (argc == 1) {
+    file = stdin;
+  } else {
+    file = fopen(argv[1], "r");
+  }
+
+  if (file == NULL) {
+    if (argc > 1)
+      fprintf(stderr, "Could not open file '%s'\n", argv[1]);
+    else
+      fprintf(stderr, "Couldn't open file\n");
+    exit(EXIT_FAILURE);
+  }
+
+  char *line;
+  size_t len = 0;
+  ssize_t read;
+  int result = 0;
+  while ((read = getline(&line, &len, file) != -1)) {
+    result += getVal(line);
+  }
+  printf("The sum of the calibration values is %d\n", result);
+  return EXIT_SUCCESS;
 }