class Stack: def __init__(self) -> None: self.items = [] def push(self,x): self.items.append(x) def pop(self): if self.items: return self.items.pop() return None def is_empty(self): return len(self.items) == 0 def is_match(s): stack = Stack() for char in s: if char in "([": stack.push(char) elif char in ")]": if not stack: return False top = stack.pop() if (char == ")" and top != "(") or (char == ']' and top != "["): return False return stack.is_empty() s = input().strip() print(str(is_match(s)).lower())