文件目录

#include <iostream>
using namespace std;
int main()
{
    int m;
    cin >> m;
    for (int i = 1; i <= m; i++)
    {
        for (int j = 1; j <= m; j++)
        {
            if (j == 1 || j == m || i == j)
                cout << "+";
            else
                cout << "-";
        }
        cout << endl;
    }
    return 0;
}