#include<stdio.h>
int main(void){
	int t,X,y;
	int s[30001];

	scanf("%d",&t);
	y=t;
    while(t--){
		scanf("%d",&X);
		if(X-7>7){
			s[t]=X-7;	
		}
		else
			s[t]=-1;
	}
	while(y--){
	    printf("%d\n",s[y]);
	}
}