A,B = raw_input(),raw_input()
counter_A,counter_B = {},{}
for c in A:
    if not c in counter_A:
        counter_A[c] = 1
    else:
        counter_A[c] += 1
for c in B:
    if not c in counter_B:
        counter_B[c] = 1
    else:
        counter_B[c] += 1
        
if counter_A == counter_B:
    print 'YES'
else:
    print 'NO'