试了很多dalao给的数据都是对的。到底哪错了？？？

#include<iostream>
#include<math.h>
using namespace std;
int main()
{
    int n,x;
    cin>>n;
    if(n==0)
    {
        cin>>x;
        cout<<x<<endl;
        return 0;
    }
    for(int i=1;i<=n+1;i++)
    {
       cin>>x;
       if(x==0)continue;
       if(i!=1&&i!=n+1&&i!=n)
       {
            if(x<0)cout<<"-";
            else if(x>0)cout<<"+";
            if(x==1||x==-1)
            {
                cout<<"x^"<<n-i+1;
            }
            else cout<<abs(x)<<"x^"<<n-i+1;
       }
       if(i==1)
       {
           if(x==1||x==-1)
            {
                cout<<"x^"<<n-i+1;
            }
           else cout<<x<<"x^"<<n-i+1;
       }
       if(i==n)
       {
           if(x<0)cout<<"-";
           else if(x>0)cout<<"+";
           if(x==1||x==-1)
            {
                cout<<"x";
            }
           else cout<<abs(x)<<"x";
       }
       if(i==n+1)
       {
           if(x<0)cout<<"-";
           else if(x>0)cout<<"+";
           cout<<abs(x);
       }
    }
    return 0;
}