[REFACTOR] [Hacker Rank] Warmup: Time Conversion solved ✅. Triying to fix sonarlint detected issues.

Author: Gonzalo Diaz

src/lib/exercises/src/hackerrank/warmup/time_conversion.c

@@ -8,31 +8,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-char *HACKERRANK_WARMUP_firstN(const char *s, unsigned long n) {
-  if (s == NULL) {
-    return NULL;
-  }
-
-  unsigned long len = strlen(s);
-  if (n > len) {
-    return NULL;
-  }
-  if (n == 0) {
-    return NULL;
-  }
-
-  char *result = (char *)malloc((n + 1) * sizeof(char));
-  if (result == NULL) {
-    return NULL;
-  }
-
-  strncpy(result, s, n);
-
-  result[n] = '\0';
-
-  return result;
-}
-
 char *HACKERRANK_WARMUP_lastN(const char *s, unsigned long n) {
   unsigned long len = strlen(s);
   if (n > len) {
@@ -58,6 +33,11 @@ char *HACKERRANK_WARMUP_getFirst(const char *s, unsigned long n) {
   return HACKERRANK_WARMUP_getStringFragment(s, strlen(s), 0, n);
 }
 
+char *HACKERRANK_WARMUP_getLast(const char *s, unsigned long n) {
+  unsigned long len = strlen(s);
+  return HACKERRANK_WARMUP_getStringFragment(s, len, len - n, n);
+}
+
 char *HACKERRANK_WARMUP_getStringFragment(const char *s, unsigned long len,
                                           unsigned long from,
                                           unsigned long to) {
@@ -82,6 +62,7 @@ char *HACKERRANK_WARMUP_getStringFragment(const char *s, unsigned long len,
 
 char *HACKERRANK_WARMUP_timeConversion(const char *s) {
   char *meridian = HACKERRANK_WARMUP_lastN(s, 2);
+  // char *meridian = HACKERRANK_WARMUP_getLast(s, 2);
 
   // char *hour_str = HACKERRANK_WARMUP_firstN(s, 2);
   char *hour_str = HACKERRANK_WARMUP_getFirst(s, 2);
@@ -98,7 +79,7 @@ char *HACKERRANK_WARMUP_timeConversion(const char *s) {
   temp_time_str = HACKERRANK_WARMUP_lastN(time_str, time_str_len - 2);
   free(time_str);
   time_str = temp_time_str;
-  temp_time_str = HACKERRANK_WARMUP_firstN(time_str, time_str_len - 2);
+  temp_time_str = HACKERRANK_WARMUP_getFirst(time_str, time_str_len - 2);
   free(time_str);
   time_str = temp_time_str;