题解 | #尼科彻斯定理#

#include <iostream>
using namespace std;
int main()
{
    //input
    int num;
    while(cin>>num)
    {
         if(num == 1)
        {
            cout<<"1"<<endl;
            return 0;
        }
        //num != 1
        int tmp = num*(num - 1)+1;
        for(int i=0; i<num -1; i++)
        {
            cout<<tmp<<"+";
            tmp += 2;
        }
        cout << tmp <<endl;
    }

    //return
    return 0;
}