# 2019 IUSB Programming Competition
# Round 1 Problem 4
# Find out if the open and closed parentheses in a string
# are properly matching
# Solution by Dana Vrajitoru
# Uses Python 3.6.2

#Find out if the parentheses are properly matching
def parenthMatch(text):
    openCount = 0
    for c in text:
        if c == "(":
            openCount += 1
        elif c == ")":
            if openCount > 0:
                openCount -= 1
            else:
                return False
    if openCount == 0:
        return True
    else:
        return False

# Testing the function
if __name__ == '__main__':
    print("Enter a string:")
    str = input()
    if parenthMatch(str):
        print("yes")
    else:
        print("no")