Secret Level
After playing Petryk's game for a long time, Kolya discovered a secret level. To access it, a secret code must be entered, and its correctness takes a while to verify. Kolya once saw Petryk enter the code and memorized it, but when he tried it himself, he was told it was incorrect. Determined to access the level, which promised many perks, Kolya sought help from the hacker Vasya. After examining the game's code, Vasya couldn't bypass the protection but figured out how to generate the code.
Here's how to obtain the code: Start with the serial number of the computer running the game. Multiply each digit of this number by itself, and write the resulting numbers consecutively to form a new number. Repeat this operation as many times as the computer has been rebooted that day. The code is the number of digits in the final number.
Input
The input consists of a single line with two integers: the number of reboots k and Kolya's computer serial number N (0 ≤ k ≤ 100, 0 ≤ N ≤ 10^13).
Output
Output a single number: the code for the secret level in Petryk's game.