Answer 1

Create a loop and in that keep adding letters of two arrays. I'm not sure about my C++ syntax.

//This is just an example snippet.
x = 6; //Length of char arrays. Both should be same.
j = 0;
for(i=0; i<(x*2);i+=2){
result[i] = input1[j];
result[i+1] = input2[j];
j++;
}