It's Binod's Birthday and all his friends want to have a great GPL for him. But Binod being so schemy, he locked his room with a secret number and given his friends a Binary string of secret number.
His friends have no knowledge about binary strings. Would you help his friends to convert given Binary String to Decimal and participate in Binod's GPL.
Binary String is a string with only '0' and '1' as it's characters.
Examples : "000101", "10101", "1", "0", "01" are Binary Strings.
"Ab3024", "123", "1A", "6", "AA" are not Binary Strings
Input Format
Output Format
Note: Secret number will always be greater than or equal to 0.