保证AC

#include <bits/stdc++.h>
using namespace std;
int main() {
    int n;
    char c;
    cin >> n >> c;
    for (int i = 1; i <= n; i++) {
        for (int j = 0; j < n - i; j++) {
            cout << " ";
        }
        for (int j = 0; j < 2 * i - 1; j++) {
            if (j == 0 || j == 2 * i - 2) {
                cout << c;
            } else {
                cout << " ";
            }
        }
        cout << endl;
    }
    for (int i = n - 1; i >= 1; i--) {
        for (int j = 0; j < n - i; j++) {
            cout << " ";
        }
        for (int j = 0; j < 2 * i - 1; j++) {
            if (j == 0 || j == 2 * i - 2) {
                cout << c;
            } else {
                cout << " ";
            }
        }
        cout << endl;
    }
}