Sum of two arrays

#1

this is link of my code and 3 test cases are not passed

#2

for(int i=size1-1;i>=1;iā€“) {
i>=0
no need to check which one is greater array
only make two pointer one on first array other on second array (both at last index i=n-1,j=m-1)
now sum these two and store in third one (from starting k=0)
at last just print array in reverse order

for(int i=n-1,j=m-1,k=0;i>=0&&j>=0;iā€“,jā€“,k++){
//do your code here
}
now check which one is left and solve accordingly

NOTE please send your code in c++ language.

#3

how much size should i take for resultant array