A=input()
B=input()

C={}
D={}

for a in A:
    if a in C:
        C[a]+=1
    else:
        C[a]=1

for b in B:
    if b in D:
        D[b]+=1
    else:
        D[b]=1

if C==D:
    print("YES")
else:
    print("NO")