题解 | #二叉树的最小深度#

/**
 * struct TreeNode {
 *    int val;
 *    struct TreeNode *left;
 *    struct TreeNode *right;
 * };
 */

class Solution {
public:
    /**
     * 
     * @param root TreeNode类 
     * @return int整型
     */
    int run(TreeNode* root) {
        // write code here
        if(root == NULL) return 0;
        int leftTreeRun = 0;
        if(root->left != NULL)
            leftTreeRun = run(root->left);
        int rightTreeRun = 0;
        if(root->right != NULL)
            rightTreeRun = run(root->right);
        if(leftTreeRun == 0 || rightTreeRun == 0)
        {
            if(leftTreeRun > rightTreeRun)
                return 1 + leftTreeRun;
            else
                return 1 + rightTreeRun;
        }
        else
        {
            if(leftTreeRun < rightTreeRun)
                return 1 + leftTreeRun;
            else
                return 1 + rightTreeRun;
        }
    }
};