Parenthesis Matching using stack

Parenthesis Matching

str = '{{{[({})[()]]}}}'

Stack s = new Stack()

i = 0
while(i< str.length()){
	c = str[i]
	if(c == '[' || c == '{' || c== '(')
		s.push(c)
	else if(!s.empty() &&
	(c == '}' && s.peek() == '{'
	||  c == ']' && s.peek() == '['
	||  c == ')' && s.peek() == '(')){
		s.pop()
	}else{
		break
	}
	i++
}

if(i == str.length() && s.empty()){
	println 'matched parenthesis'
}else{
	println 'failed to match parenthesis'
}