717. 1-bit and 2-bit Characters@python

标签：represent   rip   problem   can   spec   思路   elf   etc   lis   

We have two special characters. The first character can be represented by one bit 0. The second character can be represented by two bits (10 or 11).

Now given a string represented by several bits. Return whether the last character must be a one-bit character or not. The given string will always end with a zero.

Example 1:

Input: 
bits = [1, 0, 0]
Output: True
Explanation: 
The only way to decode it is two-bit character and one-bit character. So the last character is one-bit character.

原题地址:  1-bit and 2-bit Characters

难度:  Easy

题意: 存在两类数,一类是10或者11,另一类为0.将一个数组拆分为这两类数,判断最后一组数为0,比如上面例子,第一组数为[1,0],第二组数为[0]

思路:

对于数字1,后面的一个数字是1或者0都行,所以遇到以可以跳过1后面的值,遇到0,则移动一位

代码:

class Solution(object):
    def isOneBitCharacter(self, bits):
        """
        :type bits: List[int]
        :rtype: bool
        """
        i = 0
        while i < len(bits):
            if bits[i] == 1:
                i += 2
                if i == len(bits):
                    return False
            else:
                i += 1
        return True

时间复杂度: O(n)

空间复杂度: O(1)

717. 1-bit and 2-bit Characters@python

标签：represent   rip   problem   can   spec   思路   elf   etc   lis   

原文地址：https://www.cnblogs.com/chimpan/p/9727047.html