import java.util.*; public class Solution { int constNum=0; int num1=0; int num2=0; int minNum=0; public int lowestCommonAncestor (TreeNode root, int p, int q) { if (null == root || p==q) return 0; num1=p; num2=q; process(root); return minNum; } void process(TreeNode root){ dfs(root); //根节点都没有找到直接返回...