Maximum Total Importance of Roads LeetCode solution in JavaScript

1
var maximumImportance = function (n, roads) {
2
  const connectionCount = Array(n).fill(0);
3

4
  // Count the connections from each city
5
  // e.g. the 0th city's count will be stored at index zero in the array
6
  for (let [cityTo, cityFrom] of roads) {
7
    connectionCount[cityTo]++;
8
    connectionCount[cityFrom]++;
9
  }
10

11
  let cityToConnectionCount = [];
12
  for (let city = 0; city < n; city++) {
13
    cityToConnectionCount.push([city, connectionCount[city]]); // Store the [city, numberOfConnections]
14
  }
15

16
  // Created new array(sortedCities) for readability
17
  // sort by number of connections, the city with the greatest number of connections should be
18
  const sortedCities = cityToConnectionCount.sort((a, b) => b[1] - a[1]);
19
  // the city with the greatest importance
20

21
  const values = Array(n).fill(0);
22
  let importance = n;
23
  for (let i = 0; i < sortedCities.length; i++) {
24
    const [city, connectionCount] = cityToConnectionCount[i];
25
    values[city] = importance; // City at the 0th position array is should be the city with the greatest importance
26
    importance--;
27
  }
28

29
  // Sum the importance of each city, toCity => fromCity
30
  let res = 0;
31
  for (let [to, from] of roads) {
32
    res += values[to] + values[from];
33
  }
34

35
  return res;
36
};