输出矩形2

#include <iostream>
using namespace std;
int main () {
    int n, m;
    cin >> n >> m ;
    for (int i = 0; i < m; i++) {
        cout << "*";
    }
    cout << endl;
    for (int i = 0; i < n - 2; i++) {
        cout << "*";
        for (int j = 0; j < m - 2; j++) {
            cout << " ";
        }
        cout << "*\n";
    }
    for (int i = 0; i < m; i++) {
        cout << "*";
    }
    cout << endl;
    return 0;
}