two pointer merge for two sorted arrays
while ( l_curr + r_curr < l_c + r_c ) { if ( r_curr == r_c || ( l_curr != l_c && l_arr [ l_curr ] < r_arr [ r_curr ] ) ) output [ in ] = l_arr [ l_curr ] , l_curr ++ , in ++ ; else output [ in ] = r_arr [ r_curr ] , r_curr ++ , in ++ ; } }