LeetCode Array 45 Jump Game II 解决方法

最新推荐文章于 2021-12-31 13:02:54 发布

原创最新推荐文章于 2021-12-31 13:02:54 发布 · 117 阅读

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本文介绍了一个算法问题，即如何在给定的非负整数数组中找到从第一个元素到最后一个元素所需的最小跳跃次数。每个数组元素代表当前位置的最大跳跃长度。通过实例演示了如何实现这一目标，并提供了一段Python代码作为解决方案。

问题：Given an array of non-negative integers, you are initially positioned at the first index of the array.

Each element in the array represents your maximum jump length at that position.

Your goal is to reach the last index in the minimum number of jumps.

Example:

Input: [2,3,1,1,4]
Output: 2
Explanation: The minimum number of jumps to reach the last index is 2.
    Jump 1 step from index 0 to 1, then 3 steps to the last index.

Note:

You can assume that you can always reach the last index.

解决方法：

class Solution:
	def jump(self, nums):
		"""
		:type nums: List[int]
		:rtype: int
		"""
		position = 0
		step = 0
		while position < len(nums) - 1 :
			if position + nums[position] >= len(nums) - 1:
				step += 1
				break

			next_pos = position + 1
			max_len = 0
			for i in range(position+1, position+nums[position]+1) :
				if i + nums[i] > max_len:
					max_len = i + nums[i]
					next_pos = i

			position = next_pos
			step += 1
			
		return step