1319. Number of Operations to Make Network Connected LeetCode Solution
In this guide, you will get 1319. Number of Operations to Make Network Connected LeetCode Solution with the best time and space complexity. The solution to Number of Operations to Make Network Connected problem is provided in various programming languages like C++, Java, and Python. This will be helpful for you if you are preparing for placements, hackathons, interviews, or practice purposes. The solutions provided here are very easy to follow and include detailed explanations.
Problem Statement of Number of Operations to Make Network Connected
There are n computers numbered from 0 to n – 1 connected by ethernet cables connections forming a network where connections[i] = [ai, bi] represents a connection between computers ai and bi. Any computer can reach any other computer directly or indirectly through the network.
You are given an initial computer network connections. You can extract certain cables between two directly connected computers, and place them between any pair of disconnected computers to make them directly connected.
Return the minimum number of times you need to do this in order to make all the computers connected. If it is not possible, return -1.
Example 1:
Input: n = 4, connections = [[0,1],[0,2],[1,2]]
Output: 1
Explanation: Remove cable between computer 1 and 2 and place between computers 1 and 3.
Example 2:
Input: n = 6, connections = [[0,1],[0,2],[0,3],[1,2],[1,3]]
Output: 2
Example 3:
Input: n = 6, connections = [[0,1],[0,2],[0,3],[1,2]]
Output: -1
Explanation: There are not enough cables.
1 <= n <= 105
1 <= connections.length <= min(n * (n – 1) / 2, 105)
connections[i].length == 2
0 <= ai, bi < n
ai != bi
There are no repeated connections.
No two computers are connected by more than one cable.
Complexity Analysis
Time Complexity: O(|V| + |E|), where |E| = |\texttt{connections}|
Space Complexity: O(|V| + |E|)
1319. Number of Operations to Make Network Connected LeetCode Solution in C++
class Solution {
public:
int makeConnected(int n, vector<vector<int>>& connections) {
// To connect n nodes, we need at least n - 1 edges
if (connections.size() < n - 1)
return -1;
int numOfConnected = 0;
vector<vector<int>> graph(n);
unordered_set<int> seen;
for (const vector<int>& connection : connections) {
const int u = connection[0];
const int v = connection[1];
graph[u].push_back(v);
graph[v].push_back(u);
}
for (int i = 0; i < n; ++i)
if (seen.insert(i).second) {
dfs(graph, i, seen);
++numOfConnected;
}
return numOfConnected - 1;
}
private:
void dfs(const vector<vector<int>>& graph, int u, unordered_set<int>& seen) {
for (const int v : graph[u])
if (seen.insert(v).second)
dfs(graph, v, seen);
}
}; /* code provided by PROGIEZ */
1319. Number of Operations to Make Network Connected LeetCode Solution in Java
class Solution {
public int makeConnected(int n, int[][] connections) {
// To connect n nodes, we need at least n - 1 edges
if (connections.length < n - 1)
return -1;
int numOfConnected = 0;
List<Integer>[] graph = new List[n];
Set<Integer> seen = new HashSet<>();
for (int i = 0; i < n; ++i)
graph[i] = new ArrayList<>();
for (int[] connection : connections) {
final int u = connection[0];
final int v = connection[1];
graph[u].add(v);
graph[v].add(u);
}
for (int i = 0; i < n; ++i)
if (seen.add(i)) {
dfs(graph, i, seen);
++numOfConnected;
}
return numOfConnected - 1;
}
private void dfs(List<Integer>[] graph, int u, Set<Integer> seen) {
for (final int v : graph[u])
if (seen.add(v))
dfs(graph, v, seen);
}
} // code provided by PROGIEZ
1319. Number of Operations to Make Network Connected LeetCode Solution in Python
