import java.util.*;
public class Main {
    public static void main(String[] args) throws Exception{
        int x=0,y=0,m=0,n=0,l=0,count = 0;
        Scanner cin = new Scanner(System.in);
        x = cin.nextInt();
        y = cin.nextInt();
        m = cin.nextInt();
        n = cin.nextInt();
        l = cin.nextInt();
        
        if(m==n){
            System.out.println("Impossible");
            return;
        }
        while (x!=y) {
            count++;
            x+=m;
            y+=n;
            if (x>l-1) {
                x=x%l;
            }
            if (y>l-1) {
                y=y%l;
            }
        }
        System.out.println(count);
    }
}