A ground-control logging system stores radio callsigns and needs every callsign normalized to a canonical lowercase form before it can be matched against the registry. Given a callsign string s, produce a new string where every uppercase English letter (A-Z) has been replaced by its corresponding lowercase letter (a-z). Every other character in s (already-lowercase letters, digits, punctuation such as - and /, etc.) must be left completely unchanged, and the relative order and count of all characters must be preserved.
A single line containing the string s.
Print the normalized string on a single line.
Example 1
Input
Hotel-Delta7
Expected
hotel-delta7
Explanation
The uppercase letters 'H' and 'D' become 'h' and 'd'; the already-lowercase letters, the hyphen, and the digit '7' are unchanged, giving 'hotel-delta7'.
Example 2
Input
KX9-ALPHA/Tango7
Expected
kx9-alpha/tango7
Explanation
Every uppercase letter (K, X, A, L, P, H, A, T) is lowered to k, x, a, l, p, h, a, t respectively; the digit '9', hyphen, slash, digit '7', and the already-lowercase letters 'ango' are unchanged, giving 'kx9-alpha/tango7'.
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