def main():
    subset_judge()

def subset_judge():
    x = input()
    x = x.split()
    a = x[0]
    b = x[-1]
    count = 0
    if len(a) < len(b):
        print('No')
    else:
        for n in range(len(b)):
            if a[-1 + -n] < b[-1 + -n]:
                print('No')
                break
            count += 1
            if count == len(b):
                print('Yes')
    
if __name__ == '__main__':
    main()