Create 2092-find-all-people-with-secret.java

Author: sujal-goswami

java/2092-find-all-people-with-secret.java

@@ -0,0 +1,46 @@
+public class Solution {
+    public List<Integer> findAllPeople(int n, int[][] meetings, int firstPerson) {
+        Set<Integer> secrets = new HashSet<>(Arrays.asList(0, firstPerson)); 
+        Map<Integer, Map<Integer, List<Integer>>> timeMap = new HashMap<>(); 
+
+        for (int[] meeting : meetings) {
+            int src = meeting[0], dst = meeting[1], time = meeting[2];
+            timeMap.putIfAbsent(time, new HashMap<>());
+            timeMap.get(time).putIfAbsent(src, new ArrayList<>());
+            timeMap.get(time).putIfAbsent(dst, new ArrayList<>());
+            timeMap.get(time).get(src).add(dst);
+            timeMap.get(time).get(dst).add(src);
+        }
+
+        for (Integer time : new TreeSet<>(timeMap.keySet())) { 
+            Set<Integer> visit = new HashSet<>();
+            for (Integer src : timeMap.get(time).keySet()) {
+                if (secrets.contains(src)) {
+                    dfs(src, timeMap.get(time), visit, secrets);
+                }
+            }
+        }
+
+        return new ArrayList<>(secrets);
+    }
+
+    private void dfs(int src, Map<Integer, List<Integer>> adj, Set<Integer> visit, Set<Integer> secrets) {
+        if (visit.contains(src)) {
+            return;
+        }
+        visit.add(src);
+        secrets.add(src);
+        for (Integer nei : adj.get(src)) {
+            dfs(nei, adj, visit, secrets);
+        }
+    }
+
+    public static void main(String[] args) {
+        Solution solution = new Solution();
+        int n = 5;
+        int[][] meetings = { { 0, 1, 2 }, { 1, 2, 3 }, { 2, 3, 4 }, { 4, 5, 5 } };
+        int firstPerson = 1;
+        List<Integer> result = solution.findAllPeople(n, meetings, firstPerson);
+        System.out.println(result);
+    }
+}