717 1 Bit And 2 Bit Characters

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).

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

 

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.

 

Constraints:

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

impl Solution {
    pub fn is_one_bit_character(bits: Vec<i32>) -> bool {
        

        fn recurse(i : i32, arr : Vec<i32>) -> bool {
            //print!("{}", i);
            if i == arr.len()  as i32 - 1{
                return true;
            }

            if i > arr.len()  as i32 - 1{
                return false;
            }

            if i == arr.len() as i32 - 2 && arr[i as usize] == 1 {
                return false;
            }

            if arr[i as usize] == 0 {
                return recurse(i + 1, arr);
            } else {
                // this was 1 and that means 10 or 11
                return recurse(i + 2, arr);
            }
            

        }

        return recurse(0, bits);
    }
}