def main():
    s=input()
    stack=[]
    for i in s:
        if i=="(":
            stack.append(i)
        if i=="[":
            stack.append(i)
        if i==")":
            if not stack:
                print("false")
                return
            if stack[-1]=="(":
                stack.pop()
            else:
                print("false")
                return 
        if i=="]":
            if not stack:
                print("false")
                return
            if stack[-1]=="[":
                stack.pop()
            else:
                print("false")
                return 
    if not stack:
        print("true")
    else:
        print("false")
    
main()