1-bit and 2-bit Characters

Problem

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).

Given a binary array bits that ends with 0, return true if the last character must be a one-bit character.

Constraints

• 1 <= bits.length <= 1000
• bits[i] is either 0 or 1.

Solution

The problem 1-bit and 2-bit Characters can be solved by checking indexes for each characters. When the index of the last character matches the last bit, then the last character must be a one-bit character.

Implementation

static const int fast_io = []()
{
    std::ios::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    return 0;
}();

class Solution
{
  public:
    bool isOneBitCharacter(vector<int> &bits)
    {
        int idx = 0;
        while (idx < bits.size() - 1)
            idx += bits[idx] ? 2 : 1;

        return idx == bits.size() - 1;
    }
};