state_total_map = {
let state_total_map = new Map();
city_info.forEach(function(c) {
let key = c.state;
if (typeof state_total_map.get(key) == 'undefined') {
state_total_map.set(key, c.cnt);
} else {
state_total_map.set(key, state_total_map.get(key) + c.cnt);
}
});
state_total_map.max = d3.max(Array.from(state_total_map.values()));
return state_total_map;
}