可以这样打印三角形
```cpp
for(int i = 1;i <= n;i++){
for(int j = 1;j <= n-i;j++){
cout << " ";
}
while(a <= i*(i+1)/2){
if(a < 10) cout << 0 << a;
else cout << a;
a++;
}
```
by chenxinrong @ 2024-01-26 21:37:39