Directed Graphs and Network Flows · Easy problem

In the $5$-team tournament with results $1\to2$, $2\to3$, $3\to1$, $1\to4$, $4\to2$, $3\to4$, $1\to5$, $5\to2$, $5\to3$, $4\to5$, how many teams achieve the single highest score?