BASE64 Decoding

BASE64 writes an arbitrary byte string using only 64 characters. Split the original into groups of 3 bytes, join each group into 24 bits, then cut those bits into four 6-bit pieces. Each piece holds a value from 0 to 63, which becomes one character of the 64-character alphabet A to Z, then a to z, then 0 to 9, then + and /. If the last group has fewer than 3 bytes, pad it with zero bits before the conversion and append one = for every missing byte.

Given the BASE64 encoding of a string S, print S.

The first line contains the BASE64 encoding of the string S. S consists only of upper case letters, lower case letters and digits, and its length is between 1 and 50.

Print the string S on the first line.