Finding common elements in two arrays of different size

Question

I have a problem to find common elements in two arrays and that\'s of different size.

Take , Array A1 of size n and Array A2 o

Answer 1

The Complexity of what I give is O(N*M + N).

Also note that it is Pseudocode C And that it provides distinct values.

eg.[1,1,1,2,2,4] and [1,1,1,2,2,2,5] Will return [1,2]

The Complexity is N*M cause of the for loops

+ N cause of the checking if it already exists in the ArrayCommon[] (which is n size in case Array2[] contains data which duplicate Part of the Array1[] Assuming N is the size of the smaller Array (N < M).

int Array1[m] = { Whatever };
int Array2[n] = { Whatever };
int ArrayCommon[n] = { };

void AddToCommon(int data)
{
    //How many commons we got so far?
    static int pos = 0; 
    bool found = false;
    for(int i = 0 ; i <= pos ; i++)
    {
        //Already found it?
        if(ArrayCommon[i] == data)
        {
            found = true;
        }
    }
    if(!found)
    {
        //Add it
        ArrayCommon[pos] = data;
        pos++;
    }
}

for(int i = 0 ; i < m ; i++)
{
    for(int j = 0 ; j < n ; j++)
    {
        //Found a Common Element!
        if(Array1[i] == Array2[j])
            AddToCommon(Array1[i]);
    }
}