n,k=map(int,input().split())
S=input()

s="ABCabc"
ans=[]
for i in range(len(S)):
    if i==k-1:
        ans.append(s[s.index(S[i])+3])
    else:
        ans.append(S[i])
print("".join(ans)) n,k=map(int,input().split()) n map(int,input().split()) map int input().split() ().split () input split k S=input() S input() input s="ABCabc" s "ABCabc" ans=[] ans [] for i in range(len(S)):
    if i==k-1:
        ans.append(s[s.index(S[i])+3])
    else:
        ans.append(S[i]) i range(len(S)) range len(S) len S if i==k-1:
        ans.append(s[s.index(S[i])+3])
    else:
        ans.append(S[i]) i==k-1 i k-1 k 1 ans.append(s[s.index(S[i])+3]) ans.append ans append s[s.index(S[i])+3] s s.index(S[i])+3 s.index(S[i]) s.index s index S[i] S i 3 ans.append(S[i]) ans.append ans append S[i] S i print("".join(ans)) print "".join(ans) "".join "" join ans ans=[] [] ans n,k=map(int,input().split()) map(int,input().split()) n S=input() input() S k=map(int,input().split()) map(int,input().split()) k s="ABCabc" "ABCabc" s
n,k=map(int,input().split())
S=input()

s="ABCabc"
ans=[]
for i in range(len(S)):
    if i==k-1:
        ans.append(s[s.index(S[i])+3])
    else:
        ans.append(S[i])
print("".join(ans))
