A,B = raw_input(),raw_input() counter_A ={} for c in A: if not c in counter_A: counter_A[c] = 1 else: counter_A[c] += 1 counter_B ={} 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"