A = input()
B = input()
N = len(A)
listA = ["0" for i in range(N)]
listB = ["0" for i in range(N)]


for i in range(N):
    listA[i] = A[i]
    listB[i] = B[i]

listA.sort()
listB.sort()

solve = "NO"
for i in range(N):
    if listA == listB:
        solve = "YES"

print(solve)