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.
s = input()
n = int(input())
s = s.lower()
f = ""
for i in range(len(s)):
    o = s[i]
    if ord(o) < n + 97:
        f += o.upper()
    else:
        f += o.lower()
print(f)