The first line of the input is a string (between 1 and 50 characters long, inclusive). Each character will be a letter of English alphabet, lowercase or uppercase.

The second line of the input is an integer between 0 and 26, inclusive.
alphabet_lower=list('abcdefghijklmnopqrstuvwxyz')
s=input()
s=s.lower()
s=list(s)
count=int(input())
for i in range(len(s)):
    if alphabet_lower.index(s[i])<count:
        s[i]=s[i].upper()
print(''.join(s))