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  1. #include <stdio.h>;
  2. int Ind[300001];
  3.  
  4. int find(int p) {
  5. 	while (p != Ind[p])
  6. 		p = Ind[p];
  7. 	return p;
  8. }
  9. void Union(int p, int q) {
  10. 	int r1 = find(p);
  11. 	int r2 = find(q);
  12. 	Ind[r1] = r2;
  13. }
  14.  
  15. void main() {
  16. 	int N, a, b;
  17. 	scanf("%d", &N);
  18. 	for (int i = 1; i <= N; i++)
  19. 	{
  20. 		Ind[i] = i;
  21. 	}
  22. 	if (N == 2)
  23. 	{
  24. 		printf("1 2");
  25. 	}
  26. 	else {
  27. 		for (int i = 0; i < N-2; i++)
  28. 		{
  29. 			scanf("%d %d", &a, &b);
  30. 			Union(a, b);
  31. 		}
  32. 		int root = find(1);
  33. 		for (int i = 2; i <= N + 1; i++)
  34. 		{
  35. 			if (Ind[i] != root)
  36. 			{
  37. 				printf("%d %d", root, i);
  38. 				break;
  39. 			}
  40. 		}
  41. 	}
  42. 	exit(0);
  43. }
  44.  
  45.  
Success #stdin #stdout 0s 5284KB
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https://ideone.com/3KLAlY
language:
C (gcc 8.3)
created:
12 days ago
visibility:
public

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