void setTrafficMem() {
while (!positions.isEmpty()) {
CityLocation pos = positions.pop();
mapX = pos.x;
mapY = pos.y;
assert city.testBounds(mapX, mapY);
// check for road/rail
int tile = city.getTile(mapX, mapY);
if (tile >= ROADBASE && tile < POWERBASE) {
city.addTraffic(mapX, mapY, 50);
}
}
}
