Merge pull request #59 from caldotdev/main

fix exercise 1-12 edge cases

chapter_1/exercise_1_12/copy_io_nl.c

@@ -2,22 +2,21 @@
 
 int main()
 {
-  char c;
-  char last_char = -1;
+  int character;
+  int previous_character = EOF;
 
-  while ((c = getchar()) != EOF) {
-    if((c==' ' ||  c=='\t' ||  c=='\n')) {
-      if(c != last_char) {
+  while ((character = getchar()) != EOF) {
+    if (character == ' ' || character == '\t' || character == '\n') {
+      if (previous_character != ' ' && previous_character != '\t' && previous_character != '\n') {
         putchar('\n');
       }
     }
     else {
-      putchar(c);
+      putchar(character);
     }
 
-    last_char=c;
+    previous_character = character;
   }
 
   return 0;
 }
-