def main():
    A = list(map(int, input().split('.')))
    B = list(map(int, input().split('.')))
    for x in range(len(A)):
        if A[x] == B[x]:
            ans = 'YES'
            continue
        elif A[x] > B[x]:
            ans = 'YES'
            break
        else:
            ans = 'NO'
            break
    print(ans)
            
    

if __name__ == '__main__':
    main()