# include <stdio.h>
int main(void)
{
	int T,i,A,X;
	scanf("%d",&T);
	for(i=1;i<=T;++i)
	{
		scanf("%d",&A);
	    X=A-7;
		if(X<=7)
			printf("-1\n");
		else
			printf("%d\n",X);
	}
	return 0;
}