chall1.py

hex = input()
number = 0
base64map = {
    0:	    'A', 	16: 	'Q', 	32: 	'g', 	48: 	'w',
    1:	    'B', 	17: 	'R', 	33: 	'h', 	49: 	'x',
    2:	    'C', 	18: 	'S', 	34: 	'i', 	50: 	'y',
    3:	    'D', 	19: 	'T', 	35: 	'j', 	51: 	'z',
    4:	    'E', 	20: 	'U', 	36: 	'k', 	52: 	'0',
    5:	    'F', 	21: 	'V', 	37: 	'l', 	53: 	'1',
    6:	    'G', 	22: 	'W', 	38: 	'm', 	54: 	'2',
    7:	    'H', 	23: 	'X', 	39: 	'n', 	55: 	'3',
    8:	    'I', 	24: 	'Y', 	40: 	'o', 	56: 	'4',
    9:	    'J', 	25: 	'Z', 	41: 	'p', 	57: 	'5',
    10: 	'K', 	26: 	'a', 	42: 	'q', 	58: 	'6',
    11: 	'L', 	27: 	'b', 	43: 	'r', 	59: 	'7',
    12: 	'M', 	28: 	'c', 	44: 	's', 	60: 	'8',
    13: 	'N', 	29: 	'd', 	45: 	't', 	61: 	'9',
    14: 	'O', 	30: 	'e', 	46: 	'u', 	62: 	'+',
    15: 	'P', 	31: 	'f', 	47: 	'v', 	63: 	'/'
}


def parse(c):
    if c in ['a', 'b', 'c', 'd', 'e', 'f']:
        return ord(c) - 87
    else:
        return int(c)


def base64(n):
    str = ''
    bitmask = 63
    while(n):
        temp = n & bitmask
        n = n >> 6
        str = base64map[temp]+str
    print(str)


for c, v in enumerate(reversed(hex)):
    number += (parse(v) << (c*4))
base64(number)