What does this print for n=3?
<code>void p(int n) { if (n == 0) return; p(n - 1); System.out.print(n); p(n - 1); } </code></pre>
- Acheck_circle
1213121
- B
1
- C
123
- D
321
Explanation
Recursive in-order pattern: p(2)+3+p(2) → ((p(1)+2+p(1))+3+(p(1)+2+p(1))) → 1213121.