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# 717. 1-bit and 2-bit Characters

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:**<br>

```
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:**<br>

```
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`.

```cpp
// Greedy + One scan
bool isOneBitCharacter(vector<int>& bits) { // time: O(n); space: O(1)
    size_t n = bits.size(), i = 0;
    while (i < n - 1) {
        if (bits[i] == 1) {
            i++;
        }
        ++i;
    }
    return i == n - 1;
}
```


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