#include <iostream>
using namespace std;
long gcd(long m,long n,long l);
int main()
{
	long x,y,m,n,l;
	cin>>x>>y>>m>>n>>l;
	long q;
	if(y>x)q=y-x;
	else q=x-y;
	if(m==n||q%gcd(m,n,l)!=0)
		cout<<"Impossible";
	long a,b,c;
	a=m-n;c=y-x;
	long long k;
	for(b=1;b<l;b++)
	{
		k=a*b-c;
		if(k%l==0)
		{cout<<b;break;}
	}
	return 0;
}
long gcd(long m,long n,long l)
{
	long k;
	if(m-n<0)k=n-m;
	else k=m-n;
	long a,b;
	if(k>=l){a=k;b=l;}
	else {a=l;b=k;}
	long q,r;
	do
	{	
		q=a/b;r=a%b;
		a=b;b=r;
	}while(r!=0);
	return a;
}

• Re:如果遇到 好人帮忙 指点一下啊!(代码) (641) starwind 2008-12-07 16:06:11