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import java.util.ArrayList;
import java.util.Collections;
import java.util.Scanner;
import java.util.Stack;
import java.util.Arrays;
public class Toposort {
private static ArrayList<Integer> toposort(ArrayList<ArrayList<Integer>> adj) {
boolean[] visited = new boolean[adj.size()];
Integer[] postv = new Integer[adj.size()];
int[] clock = new int[1];
dfs(adj, visited, postv, clock);
Integer[] reverse_postv = postv.clone();
Arrays.sort(reverse_postv, Collections.reverseOrder());
ArrayList<Integer> order = new ArrayList<>();
for (int n : reverse_postv) {
order.add(Arrays.asList(postv).indexOf(n));
}
return order;
}
private static void dfs(ArrayList<ArrayList<Integer>> adj, boolean[] visited, Integer[] postv, int[] clock) {
for (int v = 0; v < adj.size(); v++) {
if (visited[v] == false)
explore(adj, v, visited, postv, clock);
}
}
private static void explore(ArrayList<ArrayList<Integer>> adj, int v, boolean[] visited, Integer[] postv, int[] clock) {
visited[v] = true;
clock[0] = clock[0] + 1;
for (int n : adj.get(v)) {
if (visited[n] == false)
explore(adj, n, visited, postv, clock);
}
postv[v] = clock[0];
clock[0] = clock[0] + 1;
}
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
int m = scanner.nextInt();
ArrayList<ArrayList<Integer>> adj = new ArrayList<>();
for (int i = 0; i < n; i++) {
adj.add(new ArrayList<Integer>());
}
for (int i = 0; i < m; i++) {
int x, y;
x = scanner.nextInt();
y = scanner.nextInt();
adj.get(x - 1).add(y - 1);
}
ArrayList<Integer> order = toposort(adj);
for (int x : order) {
System.out.print((x + 1) + " ");
}
}
static ArrayList<Integer> postOrder(ArrayList<ArrayList<Integer>> adj) {
boolean[] visited = new boolean[adj.size()];
ArrayList<Integer> postv = new ArrayList<>(Collections.nCopies(adj.size(), 0));
int[] clock = new int[1];
clock[0] = clock[0] + 1;
for (int v = 0; v < adj.size(); v++) {
exploreIterative(adj, v, visited, postv, clock);
}
return postv;
}
private static void exploreIterative(ArrayList<ArrayList<Integer>> adj, int v, boolean[] visited, ArrayList<Integer> postv, int[] clock) {
if (visited[v] == false) {
// prev[v] = clock[0]
boolean[] inStack = new boolean[adj.size()];
clock[0] = clock[0] + 1;
visited[v] = true;
inStack[v] = true;
Stack<Integer> vertexStack = new Stack<>();
vertexStack.push(v);
while (vertexStack.isEmpty() == false) {
int tempVertex = vertexStack.peek();
// if (tempVertex != v) {
// visited[tempVertex] = true;
// // prev[v] = clock[0]
// clock[0] = clock[0] + 1;
// }
if (tempVertex != v && visited[tempVertex]) {
vertexStack.pop();
continue;
}
if (adj.get(tempVertex).size() == 0) {
if (tempVertex != v) {
// prev[tempVertex] = clock[0];
clock[0] = clock[0] + 1;
visited[tempVertex] = true;
}
postv.set(tempVertex, clock[0]);
clock[0] = clock[0] + 1;
vertexStack.pop();
} else {
boolean allEdgesFollowed = true;
for (int i : adj.get(tempVertex)) {
if (visited[i] == false) {
// visited[i] = true;
// prev[i] = clock[0]
if (inStack[i] == false) {
inStack[i] = true;
vertexStack.push(i);
}
allEdgesFollowed = false;
}
}
if (allEdgesFollowed) {
visited[tempVertex] = true;
if (postv.get(tempVertex) == 0)
postv.set(tempVertex, clock[0]);
clock[0] = clock[0] + 1;
vertexStack.pop();
}
}
}
}
}
}
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