Dr. Strange has developed some new powers since he has started programming. Now if a villan throws a 1 at him, he absorbs it and add it to his already existing binary string s. There are n villans and each of them throws a '1' at him. At each point you have to detemine the resulting string s.
First line of input contains n denoting the number of enemies. Each of the next n lines contain an integer l and a string s denoting the length of the existing binary string and the string itself.
For each of the n lines print a string denoting the resulting binary string at each steps.