9.6(собственные числа)

#include <iostream>
#include <stdlib.h>     /* srand, rand */
#include <time.h>       /* time */
#include <vector>
#include <algorithm>    // std::sort

using namespace std;


int main()
{
    int n,m,p,numb=0;
    cin>>n;
    int *arr1=new int[n];
    for (int i=0;i<n;i++)
    {
        cin>>arr1[i];
    }
    cin>>m;
    int *arr2=new int[m];
    for (int i=0;i<m;i++)
    {
        cin>>arr2[i];
    }
    cin>>p;
    int *arr3=new int[p];
    for (int i=0;i<p;i++)
    {
        cin>>arr3[i];
    }
    for (int i=0,j=0,k=0;i<n || j<m || k<p;)
    {
        if (arr1[i]==arr2[j] && arr1[i]==arr3[k])
            {numb++;i++;j++;k++;}
        else
            if (i<n && arr1[i]<=arr2[j] && arr1[i]<=arr3[k])
                {i++;}
        else
            if (j<m && arr2[j]<=arr1[i] && arr2[j]<=arr3[k])
                {j++;}
        else
            if (k<p && arr3[k]<=arr1[i] && arr3[k]<=arr2[j])
                {k++;}
        else
          break;
    }
    cout<<numb;
}