Consider the following C functions.

int tob (int b, int* arr) {
    int i;
    for (i = 0; b>0; i++)  {
        if (b%2)  arr [i] = 1;
        else      arr[i] = 0;
        b = b/2;
    }
    return (i);
}
 
int pp(int a, int b)  {
    int  arr[20];
    int i, tot = 1, ex, len;
    ex = a;
    len = tob(b, arr);
    for (i=0; i<len ; i++) {
         if (arr[i] ==1)
             tot = tot * ex;
         ex= ex*ex;
    }
return (tot) ;
}

The value returned by pp(3,4) is ________ .