string.atoi()

string.atoi(s[, base]) → int[source]

Return the integer represented by the string s in the given base, which defaults to 10. The string s must consist of one or more digits, possibly preceded by a sign. If base is 0, it is chosen from the leading characters of s, 0 for octal, 0x or 0X for hexadecimal. If base is 16, a preceding 0x or 0X is accepted.