function initHashMap() {
  const keys = Object.keys(testHashMap);
  keys.forEach((key) => {
    Object.defineProperty(testHashMap[key], "_visited", {value: false, enumerable: false, writable: true});
  });
}
/**
 * To init the map, define a '_visited' property on the node, which is writable but not enumerable.
 */
To init the map, define a '_visited' property on the node, which is writable but not enumerable.
To init the map define a ' _visited ' property on the node which is writable but not enumerable .
function initHashMap() {
  const keys = Object.keys(testHashMap);
  keys.forEach((key) => {
    Object.defineProperty(testHashMap[key], "_visited", {value: false, enumerable: false, writable: true});
  });
}
function initHashMap ( ) { const keys = Object . keys ( testHashMap ) ; keys . forEach ( ( key ) => { Object . defineProperty ( testHashMap [ key ] , "_visited" , { value : false , enumerable : false , writable : true } ) ; } ) ; }
To init the map, define a '_visited' property on the node, which is writable but not enumerable.
To init the map define a ' _visited ' property on the node which is writable but not enumerable .