Please input a positive integer $($input a negative value or zero to quit$)$: $7$

The greatest factor $($not including self$)$ of this integer is: $1$

Please input a positive integer $($input a negative value or zero to quit$)$: $12$

The greatest factor $($not including self$)$ of this integer is: $6$

Please input a positive integer $($input a negative value or zero to quit$)$: $15$

The greatest factor $($not including self$)$ of this integer is: $5$

Please input a positive integer $($input a negative value or zero to quit$)$: $-1$

Bye!