input_routes.rou.xml

<routes>
    <vType id="bus" sigma="0" maxSpeed="3"/>
    <route id="busroute" edges="a b c -c -b -a a b c -c -b -a a b c -c -b -a" repeat="2" cycleTime="150">
        <stop busStop="busStop_a"  duration="10" until="20"/>
        <stop busStop="busStop_c"  duration="10" until="40"/>
        <stop busStop="busStop_-c" duration="10" until="60"/>
        <stop busStop="busStop_-a" duration="10" until="80"/>
    </route>
    <flow id="bus" type="bus" begin="0" number="2" period="100" route="busroute"/>
    <vehicle id="bus_single" type="bus" depart="300" route="busroute"/>
</routes>