Generate Parentheses 2021-06-06 19:26
private List<String> res = new ArrayList<>();
public List<String> generateParenthesis(int n) {
dfs("", n, 0, 0);
return res;
}
private void dfs(String ans, int n, int leftCount, int rightCount) {
if (rightCount > leftCount || leftCount > n) {
return;
}
if (leftCount == rightCount && rightCount == n) {
res.add(ans);
}
dfs(ans + "(", n, leftCount + 1, rightCount);
dfs(ans + ")", n, leftCount, rightCount + 1);
}
| Runtime | Memory |
|---|---|
| 1 ms | 38.9 MB |
EOF