Find Eventual Safe States LeetCode solution in Java

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class Solution {
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  public List<Integer> eventualSafeNodes(int[][] graph) {
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    int n = graph.length;
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    List<Integer> ans = new ArrayList<>();
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    boolean visited[] = new boolean[n];
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    boolean dfsVisited[] = new boolean[n];
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    boolean nodeCycles[] = new boolean[n];
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    for (int i = 0; i < n; i++) {
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      if (visited[i] == false) {
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        isCycle(i, graph, dfsVisited, visited, nodeCycles);
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      }
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    }
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    for (int i = 0; i < nodeCycles.length; i++) {
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      if (nodeCycles[i] == false) ans.add(i);
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    }
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    return ans;
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  }
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  public boolean isCycle(
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      int node, int graph[][], boolean dfsVisited[], boolean visited[], boolean[] nodeCycles) {
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    visited[node] = true;
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    dfsVisited[node] = true;
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    for (int adjNode : graph[node]) {
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      if (visited[adjNode] == false) {
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        if (isCycle(adjNode, graph, dfsVisited, visited, nodeCycles))
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          return nodeCycles[node] = true;
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      } else if (visited[adjNode] == true && dfsVisited[adjNode] == true) {
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        return nodeCycles[node] = true;
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      }
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    }
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    dfsVisited[node] = false;
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    return false;
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  }
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}