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import java.util.ArrayList;
import java.util.Scanner;
public class Reachability {
static int reach(ArrayList<ArrayList<Integer>> adj, int x, int y) {
ArrayList<Integer> visited = new ArrayList<>();
if (x == y)
return 1;
explore(adj, visited, x, y);
if (visited.contains(y))
return 1;
return 0;
}
private static void explore(ArrayList<ArrayList<Integer>> adj, ArrayList<Integer> visited, int x, int y) {
visited.add(x);
if (x == y)
return;
for (int n : adj.get(x)) {
if (!visited.contains(n))
explore(adj, visited, n, y);
}
}
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<ArrayList<Integer>>();
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);
adj.get(y - 1).add(x - 1);
}
int x = scanner.nextInt() - 1;
int y = scanner.nextInt() - 1;
System.out.println(reach(adj, x, y));
}
}
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