markov chain with ant in a triangle

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An ant walks from vertex to vertex of a triangle in a clockwise direction with probability: $\begin{cases} P = \frac{1}{2} \text{ if it's at vertex 1} \\ P = \frac{3}{4} \text{ if it's at vertex 2} \\ P = 1 \text{ if it's at vertex 3} \end{cases}$

What is the PTM of this Markov chain?

I think it has 3 states (the vertices) but the way I'm understanding the probabilities show that rows don't sum to 1 which is most likely incorrect.

For example, I set the transition probability from state $1$ to state $2$ as $\frac{1}{4}$ because that's the probability it takes the ant to travel there?

$\hspace{7.75cm}$1$\hspace{2mm}$ 2$\hspace{2mm}$ 3

$$\begin{bmatrix} 0 & \frac{1}{4} & 0 \\ 0 & 0 & \frac{1}{4} \\ \frac{1}{2} & 0 & 0 \end{bmatrix}$$

Please clarify

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You also need to consider the alternative cases. It goes to the clockwise state with probability $p$ and counterclockwise with probability $1-p$.

$\hspace{7cm}$1$\hspace{9mm}$ 2$\hspace{9mm}$ 3

$$\begin{bmatrix} 0 & \frac{1}{2} & 1-\frac{1}{2} \\ 1-\frac{3}{4} & 0 & \frac{3}{4} \\ 1 & 1-1 & 0 \end{bmatrix}$$