#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll exgcd(ll a,ll b,ll &x,ll &y){
	if(b==0){
		x=1,y=0;
		return a;
	}ll d=exgcd(b,a%b,x,y),t=x;
	x=y;
	y=t-a/b*y;
	return d;
}int main(){
	ll x,y,m,n,L,rx,ry;
	scanf("%lld%lld%lld%lld%lld",&x,&y,&m,&n,&L);
	ll d=exgcd(n-m,L,rx,ry);
	rx*=(x-y)/d;
	if(m==n||(x-y)%d!=0)printf("Impossible");
	else cout<<(rx%(L/d)+L/d)%(L/d);
	return 0;
}

我帮我同学问一下，他被禁言了