C++ :

#include<bits/stdc++.h>
using namespace std;
int main()
{
int n;
cin>>n;
for(int i=n;i>=0;i--)
{
	int x;
	cin>>x;
	if(x==0)	continue;
	if(i!=n and x>0)	cout<<"+";
	if(i==0)
	{
		cout<<x;
		continue;
	}
	if(abs(x)!=1)		cout<<x;
	if(x==-1)			cout<<"-";
	if(i!=1)			cout<<"x^"<<i;
	else				cout<<"x";

}





}