Two Counters

You have $2$ counters $a$ and $b$, both initialised as $0$. You also have a score initialised as $0$. At the start of every minute from minute $1$ to minute $N$, you **must** increase **either** $a$ or $b$ by $1$. Additionally, there are $M$ events. The $i^{th}$ event happens at minute $T_i+0.5$ and has type $C_i$ $(C_i \in \{1, 2\})$. At each event, the counters or the score is updated as: ```