n=int(input())
#S = [input().split() for i in range(n)] 
S=str(input())
cnt=[0]*26
"""
for i in range(len(S)):
    cnt[S[i]-"A"]+=1

for i in range (26):
    print(cnt[i],end='')
"""
for i in range (26):
    ord_s=ord('A')
    chr_s = chr(ord_s+i)
    #print(chr_s)
    print(S.count(chr_s),end='')