How to solve it by computer 4.4

Program C++

#include <iostream>

using namespace std;

int main(int argc, char** argv) {

int a[20],n;

cout<<"Batas : ";

cin>>n;

for (int i=0;i<n;i++){

cout<<"Data : ";

cin>>a[i];

}

for (int i=0;i<n;i++){

if(a[i]==a[i+1])

cout<<a[i];

else if(a[i-1]==a[i])

cout<<"";

else if(a[i]==a[i+2])

cout<<a[i];

else if(a[i-2]==a[i])

cout<<"";

else if(a[i]==a[i+3])

cout<<a[i];

else if(a[i-3]==a[i])

cout<<"";

else if(a[i]==a[i+4])

cout<<a[i];

else if(a[i-4]==a[i])

cout<<"";

else if(a[i]==a[i+5])

cout<<a[i];

else if(a[i-5]==a[i])

cout<<"";

else 

cout<<a[i];

}

/* for (int i=0;i<n;i++){ 

cout<<a[i]<<" ";}*/

return 0;

}