Google | Phone Screen | Remove Duplicate Spaces
Anonymous User
1427
GooglePhone ScreeningInterview

Hi,

Following is the question asked in the phone interview .
Given an array of characters, remove duplicate spaces
eg:
input : {'a', 'b', ' ', ' ', 'c' } Output : {'a', 'b', ' ', 'c'}
input : {'a', 'b', ' ', ' ', ' ' } Output : {'a', 'b', ' '}

My Approach 1 :

public List<Character> removeDupSpaces(List<Character> chars) {
List<Character> st = new ArrayList<Character>();
int count = 0;
for(Character c : chars) {
   if(c != ' ') {
   	st.add(c);
   } else {
      count++;
      if(count == 1){
   		st.add(c);
   	}
   }
}
return st;
}

My Approach 2 : Wanted to solve using 2 pointer approach without using extra space but not successfull :(

public void removeDupSpaces(List<Character> chars) {
      int reader = 0;
      int writer  = 0;
      int count = 0;
  while(reader<chars.size()) {
      if(chars.get(reader) != ‘ ‘) {
       reader++;
       writer++;
     } else { 
       count ++;
       reader++;
     if(count > 1) {
       writer++;
      chars.set(writer, chars.get(reader));
chars.remove(chars.get(reader));
    }
  }
   if(reader == chars.size()) { reader = 0};
}
}

Any help would be appreciated.

Thanks

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