var mymap = L.map("hogemap").setView([38.891, 139.824], 16);
L.tileLayer('//{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
 attribution:
   '&copy; <a href="http://osm.org/copyright">OpenStreetMap</a> contributors'
}).addTo(mymap);
L.marker([38.891, 139.824]).addTo(mymap);

document.addEventListener('DOMContentLoaded', mymap)