class CharacterArrayList {

	private char[] array = null;	
	private int size = 0;

	public CharacterArrayList(int length) {
		array = new char[length];
	}

	public int size() {
		return size;
	}

	public void add(char c) {
		if (size == array.length) {
			return;
		}

		for(int i = 0; i < array.length; i++) {
			if(array[i] == '\0') {
				array[i] = c;
				size++;
				return;
			}
		}
	}

	@Override
	public String toString() {

		int count = 0;
		String str = "[";
		for(int i = 0; i < array.length; i++) {
			if(array[i] != '\0') {
				str += array[i];
				count++;
				if (count != size) {
					str += ",";
				}
			}
		}
		str += "]";
		return str;

	}

	public char set(int index, char c) {
		if(index < 0 || index >= array.length) {
			return '\0';
		}

		if (array[index] == '\0') {
			size++;
		}


		char orig = array[index];
		array[index] = c;
		return orig;
	}

	public char get(int index) {
		if(index < 0 || index >= array.length) {
			return '\0';
		}
	
		return array[index];
	}

	public boolean contains(char c) {
		for(int i = 0; i < array.length; i++) {
			if(array[i] == c) {
				return true;
			}
		}
		return false;
	}

	public int indexOf(char c) {
		for(int i = 0; i < array.length; i++) {
			if (array[i] == c) {
				return i;
			}
		}
		return -1;
	}

}