Given a list of transactions, where each transaction is represented as $transactions[i] = [from_i,~ to_i,~amount_i]$, indicating that the person $from_i$ gave $amount_i$ to the person $to_i$. Return the minimum number of transactions needed to settle all debts.

Constraints:

• $1\leq$ transactions.length $\leq10$

• transactions[i].length $==3$

• $0 \leq$ fromi, toi $\leq10$

• $1\leq$ amounti $\leq100$

• fromi $\neq$ toi