#include<iostream>
#include<stdio.h>
#include<stdlib.h>
using namespace std;
int main(){
	int t;
	int x;
	cin>>t;
	while(t--){
		cin>>x;
		
		int temp;
		temp = x-7;
		if(temp<=7){
			printf("-1\n");
		}
		else{
			printf("%d\n",temp);
		}
	
	}
}