wrong answer, but I do't know why! help, please

#include<iostream>
using std::cout;
using std::cin;
using std:: endl;
int main(){
    int res = 0;
    int n1, n2, n3;
    cin >> n1;
    unsigned *arr1 = new unsigned[n1];


    unsigned temp[100];
    for(int i = 0; i < n1; ++i){
        cin >> arr1[i];
    }
    cin >> n2;
    unsigned *arr2 = new unsigned[n2];
    for(int i = 0; i < n2; ++i){
        cin >> arr2[i];
    }
    cin >> n3;
    unsigned *arr3 = new unsigned[n3];
    for(int i = 0; i < n3; ++i){
        cin >> arr3[i];
    }
    int sum = 0;
    for(int i = 0; i < n1; i++){
        for(int j = 0; j < n2; ++j){
            if(arr2[j] == arr1[i])
            temp[i]= arr2[j];
            sum++;
        }
    }
    int sum1 = 0;
    for(int i = 0; i < sum; i++){
        for(int j = 0; j < n3; ++j){
            if(arr3[j] == temp[i])
            sum1++;
        }
    }
cout << sum1 << endl;
    delete[]arr1;
    delete[]arr2;
    delete[]arr3;
system("PAUSE");
return 0;
}