prime

Consider the sequence of prime numbers: p₁=2, p₂=3, p₃=5, p₄=7, ... .
The integer n (n>=2) has the p-writing a₁a₂...a_k-1a_k if it can be written in the following form:
n=a₁*p₁+a₂*p₂+...+a_k-1*p_k-1+a_k*p_k, where a_k=1, and a_i can be either 0 or 1, for any i, 0<i<k.

E.g. n=10 has both p-writing 111, because 10=1*2+1*3+1*5, as well as p-writing 0101 because 10=0*2+1*3+0*5+1*7.

Task

Write a program that reads the p-writing of an integer and calculates the decimal value of this integer.

Input data

The first line of input file prime.in contains the p-writing of a positive integer.

Output data

The output file prime.out will contain a single line on which your program should write the decimal value of the number corresponding to the p-writing in the input file.

Constraints

• The length of the p-writing is k <= 3000
• Any line ends with a newline character.

Example

 Time limit: 0.1 seconds/test

prof. Boriga Radu
“Spiru Haret” National College - Bucharest
Contact: r_boriga@yahoo.com