https://leetcode.com/problems/minimum-depth-of-binary-tree/description/
Given a binary tree, find its minimum depth.
The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.
package go.jacob.day807;
/**
* 111. Minimum Depth of Binary Tree
* @author Jacob
*
*/
public class Demo5 {
/*
* 方法一
*/
public int minDepth(TreeNode root) {
if(root == null) return 0;
int left = minDepth(root.left);
int right = minDepth(root.right);
return (left == 0 || right == 0) ? left + right + 1: Math.min(left,right) + 1;
}
/*
* 方法二
*/
public int minDepth_1(TreeNode root) {
if(root==null)
return 0;
if(root.left==null)
return 1+minDepth(root.right);
if(root.right==null)
return 1+minDepth(root.left);
return 1+Math.min(minDepth(root.left), minDepth(root.right));
}
}
