последовательность ()

def check2(s):
    stack3 = []
    pod_mat = {')': '(', '}': '{', ']': '['}
    for i in s:
        if i in pod_mat.values():
            stack3.append(i)
        elif i in pod_mat:
            if not stack3 or stack3.pop() != pod_mat[i]:
                return False
        else:
            return False
    return not stack3

s = input()
if (check2(s)) == True:
    print("yes")
else:
    print("no")