717. 1-bit and 2-bit Characters

　　　　这是一道简单题

　　题目：

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.

Example 2:

Input: 
bits = [1, 1, 1, 0]
Output: False
Explanation: 
The only way to decode it is two-bit character and two-bit character. So the last character is NOT one-bit character.

Note:
1 <= len(bits) <= 1000.
bits[i] is always 0 or 1.

 

　　思路:

　　　　这道题挺简单的，主要是需要理解题目，用一个while循环，遇见1就把索引加2，否则加1，如果在循环中碰见索引等于长度-1，那么就返回True,否则循环结束就返回False

　　代码:

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