[Leetcode - Medium] Number of Operations to Make Network Connected

bangdori/Number of Operations to Make Network Connected.js

@@ -0,0 +1,44 @@
+/**
+ * @param {number} n
+ * @param {number[][]} connections
+ * @return {number}
+ */
+var makeConnected = function (n, connections) {
+  if (connections.length < n - 1) return -1;
+
+  const visited = new Array(n).fill(false);
+  const graph = makeGraph(n, connections);
+  let answer = 0;
+
+  for (let i = 0; i < n; i++) {
+    if (visited[i]) continue;
+
+    dfs(i, graph, visited);
+    answer += 1;
+  }
+
+  return answer - 1;
+};
+
+function makeGraph(n, connections) {
+  const graph = Array.from({ length: n }, () => []);
+
+  for (const connection of connections) {
+    const [src, dest] = connection;
+
+    graph[src].push(dest);
+    graph[dest].push(src);
+  }
+
+  return graph;
+}
+
+function dfs(computer, graph, visited) {
+  if (visited[computer]) return;
+  visited[computer] = true;
+
+  for (const next of graph[computer]) {
+    if (visited[next]) continue;
+    dfs(next, graph, visited);
+  }
+}