# 717.1 Bit and 2 Bit Characters

**717.1 Bit and 2 Bit Characters**

难度:Easy

> 有两种特殊字符。第一种字符可以用一比特0来表示。第二种字符可以用两比特(10 或 11)来表示。

现给一个由若干比特组成的字符串。问最后一个字符是否必定为一个一比特字符。给定的字符串总是由0结束。

```
示例 1:

输入: 
bits = [1, 0, 0]
输出: True
解释: 
唯一的编码方式是一个两比特字符和一个一比特字符。所以最后一个字符是一比特字符。
示例 2:

输入: 
bits = [1, 1, 1, 0]
输出: False
解释: 
唯一的编码方式是两比特字符和两比特字符。所以最后一个字符不是一比特字符。
注意:

1 <= len(bits) <= 1000.
bits[i] 总是0 或 1.
```

直接遍歷一遍，當遇到1開頭的前進兩步，遇到0則前進一步，看最後終止的時候在哪來判斷最後一位是否爲1比特。

```
class Solution {
public:
    bool isOneBitCharacter(vector<int>& bits) {
        int start=0;
        while(start<bits.size()-1)
        {
            if(bits[start]) start+=2;
            else start+=1;
        }
        return start==bits.size()-1;
    }
};
```

> 执行用时 :4 ms, 在所有 C++ 提交中击败了95.56%的用户\
> 内存消耗 :8.8 MB, 在所有 C++ 提交中击败了72.51%的用户


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