fork download
copy 
  1. import java.util.*;
  2. import java.io.*;
  3. import java.math.*;
  4.  
  5. class Main {
  6. 	static int i,j,n,m,x[] = new int[2505],y[] = new int[2505];
  7. 	static int a[] = new int[4100005]; 
  8. 	static Map<Long, Integer> hashmap = new HashMap<Long, Integer>();
  9. 	static int gcd(int a, int b)
  10. 	{
  11. 		if (b == 0) return a;
  12. 		return gcd(b,a%b);
  13. 	}
  14. 	static int Abs(int x)
  15. 	{
  16. 		if (x > 0)
  17. 			return x;
  18. 		return -x;
  19. 	}
  20. 	public static void main(String[] args) throws IOException{
  21. 		Scanner sc = new Scanner(System.in);//new File("input.txt"));
  22. 	    PrintWriter pw = new PrintWriter(System.out);//new File("output.txt"));
  23. 	    n = sc.nextInt();
  24. 	 	for (i = 2; i <= 2000; i++)
  25. 			a[i*i-i] = i;
  26. 	 	for (i = 0; i < n; i++)
  27. 	 	{
  28. 			x[i] = sc.nextInt(); y[i] = sc.nextInt();
  29. 	 	}
  30. 		for (i = 0; i < n; i++)
  31. 		{
  32. 			for (j = 0; j < n; j++)
  33. 			if (i != j)
  34. 			{
  35. 				int kc = y[j] - y[i];
  36. 				int kz = x[j] - x[i];
  37. 				int bc = y[i]*(x[j] - x[i]) - x[i]*(y[j]-y[i]);
  38. 				int bz = x[j] - x[i];
  39. 				if (kz != 0)
  40. 				{
  41. 				int tmp = gcd(Abs(kc), Abs(kz));
  42. 				kc /= tmp; kz /= tmp;
  43. 				if (kc < 0)
  44. 				{
  45. 				   kc = -kc; kz = -kz;
  46. 				}
  47. 				if (kc == 0)
  48. 				   kz = 1;
  49. 	            tmp = gcd(Abs(bc), Abs(bz));
  50. 				bc /= tmp; bz /= tmp;
  51. 				if (bc < 0)
  52. 				{
  53. 				   bc = -bc; bz = -bz;
  54. 				}
  55. 				if (bc == 0)
  56. 				   bz = 1;
  57. 	            }
  58. 	            else
  59. 	            kc = bc = x[i];
  60. 				long hsh = (long)bc*270000*100000 + (long)bz*9000000 + (long)kc*300 + (long)kz;
  61. 				int k = 0;
  62. 				if (hashmap.containsKey(hsh))
  63. 				{
  64. 					k = hashmap.get(hsh);
  65. 				}
  66. 					hashmap.put(hsh, k+2);
  67. 			}
  68. 		}
  69. 		long ans = ((long)n*(n-1)*(n-2))/6;
  70. 		Iterator <Long> itr = hashmap.keySet().iterator();
  71. 		while (itr.hasNext())
  72. 		{
  73. 			int tmp = hashmap.get(itr.next());
  74. 			tmp = a[tmp/2];
  75. 			ans -= ((long)tmp*(tmp-1)*(tmp-2))/6;
  76. 		}
  77. 		pw.println(ans);
  78. 	   pw.close();
  79. 	}
  80. }
  81.  
Runtime error #stdin #stdout #stderr 0.12s 380608KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
Standard output is empty
stderr
copy 
Exception in thread "main" java.util.NoSuchElementException
	at java.util.Scanner.throwFor(Scanner.java:907)
	at java.util.Scanner.next(Scanner.java:1530)
	at java.util.Scanner.nextInt(Scanner.java:2160)
	at java.util.Scanner.nextInt(Scanner.java:2119)
	at Main.main(Main.java:23)
https://ideone.com/guIiI3
language:
Java (12.0.1)
created:
9 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!