# Perl support Hexadecimal (start with 0x)
#  0xff
#
# Binay (starts with 0b)
#  0b01001011001
#
# and Octal (starts with 0 and all numbers) notations
#  0367
#
# From perldata:
#  You are allowed to use underscores (underbars) in numeric literals between
#  digits for legibility. You could, for example, group binary digits by threes
#  (as for a Unix-style mode argument such as 0b110_100_100) or by fours (to
#  represent nibbles, as in 0b1010_0110) or in other groups.
from string import atoi, atof

def convert(perlstr):
    perlstr = perlstr.replace('_', '')
    if perlstr[:2] == '0x':
        num = atoi(perlstr[2:], 16)
    elif perlstr[:2] == '0b':
        num = atoi(perlstr[2:], 2)
    elif perlstr[0] == '0' and len(perlstr) > 1:
        num = atoi(perlstr[1:], 8)
    else:
        splitted = perlstr.lower().split('e')
        perlstr = splitted[0]
        if '.' in perlstr:
            num = atof(perlstr)
        else:
            num = atoi(perlstr)
        if len(splitted) == 2:
            return num * (10 ** atoi(splitted[1]))
    return num

if __name__ == '__main__':
    print '42_000_000 ->',      convert('42_000_000')
    print '0xdead_beef ->',     convert('0xdead_beef')
    print '0b111_010_110 ->',   convert('0b111_010_110')
    print '0777 ->',            convert('0777')
    print '3.14e100 ->',        convert('3.14e100')