记个答案
输入：3
输出： A
BAB
CBABC
include <bits/stdc++.h>
using namespace std;
int main()
{
int a;
cin >> a;
for (int i = 1; i <= a; i++)
{
for (int j = 1; j <= a - i; j++)
cout << " ";
for (int j = 1; j <= 2 * i - 1; j++)
cout << char (65 + abs (i - j));
cout << endl;
}
return 0;