Bit calculator

In this kata your task is to create bit calculator. Function arguments are two bit representation of numbers ("101","1","10"...), and you must return their sum in decimal representation.

Test.expect(calculate("10","10") == 4);
Test.expect(calculate("10","0") == 2);
Test.expect(calculate("101","10") == 7);

parseInt and some Math functions are disabled.

Those Math functions are enabled: pow,round,random.

https://www.codewars.com/kata/bit-calculator