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  1. public class DoubleLive {
  2.  
  3. 	final int MOD = 1000 * 1000 * 1000 + 7;
  4.  
  5. 	long my_pow(long a, long b) {
  6. 		long r = 1;
  7. 		while(b > 0) {
  8. 			if(b % 2 == 1) r = r * a % MOD;
  9. 			a = a * a % MOD;
  10. 			b /= 2;
  11. 		}
  12. 		return r;
  13. 	}
  14. 	long my_inv(long a) { return my_pow(a, MOD - 2); }
  15.  
  16. 	public int findEV(int B, int H, int T) {
  17. 		System.out.println(480 * my_inv(7) % MOD);
  18. 		long p[][][] = new long[2][B+1][H+B+1];
  19. 		p[0][B][H] = 1;
  20. 		long answer = 0;
  21. 		long memo_inv[] = new long[2*B+H+1];
  22. 		for(int i = 1; i <= 2 * B + H; ++i)
  23. 			memo_inv[i] = my_inv(i);
  24. 		for(int firstBearWounded = 0; firstBearWounded <= 1; ++firstBearWounded)
  25. 			for(int twos = B; twos >= 0; --twos)
  26. 				for(int ones = H+B; ones >= 1; --ones) {
  27. 					long my_p = p[firstBearWounded][twos][ones];
  28. 					if(my_p == 0) continue;
  29. 					int alive = twos + ones;
  30. 					if(2 * B + H - (2 * twos + ones) == T) {
  31. 						answer = (answer + my_p * alive) % MOD;
  32. 						continue;
  33. 					}
  34. 					my_p = my_p * memo_inv[alive] % MOD;
  35. 					// a single dies
  36. 					int a = ones - 1;
  37. 					if(firstBearWounded == 1) --a;
  38. 					if(a >= 1) {
  39. 						p[firstBearWounded][twos][ones-1] += my_p * a;
  40. 						p[firstBearWounded][twos][ones-1] %= MOD;
  41. 					}
  42. 					// a double becomes a single
  43. 					a = twos;
  44. 					if(firstBearWounded == 0) --a;
  45. 					if(a >= 1) {
  46. 						p[firstBearWounded][twos-1][ones+1] += my_p * a;
  47. 						p[firstBearWounded][twos-1][ones+1] %= MOD;
  48. 					}
  49. 					// the fixed bear gets wounded
  50. 					if(firstBearWounded == 0) {
  51. 						p[1][twos-1][ones+1] += my_p;
  52. 						p[1][twos-1][ones+1] %= MOD;
  53. 					}
  54. 				}
  55. 		answer = answer * B % MOD * H % MOD;
  56. 		return (int) answer;
  57. 	}
  58. }
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
Main.java:1: error: class DoubleLive is public, should be declared in a file named DoubleLive.java
public class DoubleLive {
       ^
1 error
stdout 
Standard output is empty
https://ideone.com/zxAKiF
language:
Java (HotSpot 12)
created:
6 years ago
visibility:
secret

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