subtask 3未过求条

#include <iostream>
#include <vector>
using namespace std;

int main() {
    int T;
    cin >> T;
    while (T--) {
        int n;
        cin>>n;
        for(int i=1,x;i<=n;i++) cin>>x;
        if(n==1){
        	cout<<-1<<endl;
        	continue;
		} 
        if(n%2==1){
        	int ze=n/2;
        	if(ze%2==1) {
	        	cout<<-1<<endl;
	        	continue;
			} 
        	for(int i=1;i<=ze;i++) cout<<2*i-1<<" "<<2*i<<endl;
        	cout<<0<<" "<<0<<endl;
        	ze/=2;
        	for(int i=1;i<ze;i++) cout<<"1 0\n2 0\n";
        	cout<<1<<" "<<n<<endl;
		}else
			for(int i=1;i<n;i++)
				cout<<(i&1)<<" "<<i+1<<endl;
    }
    return 0;
}