Computer went into infinite loop of thinking at the edge of defeat

The following is the moveList. After the last move computer went into an infinite loop of thinking where I waited for nearly 2 hours.Then I had to cancel as it was not coming back.

[Site "Chess.com"]
[Date "2011.06.05"]
[White "Player"]
[Black "Computer - Hard"]
 1. e4 d5 2. exd5 Qxd5 3. Nc3 Qd6 4. Nb5 Qc6 5. d4 Na6 6. c3 Nf6 7. h3 Bd7 8. Nf3 Qb6 9. Qe2 O-O-O 10. b4 h5 11. Ne5 Be8 12. g3 Nxb4 13. cxb4 e6 14. a3 Bxb5 15. Qxb5 Rxd4 16. Be3 Qxb5 17. Bxb5 Rd5 18. Nxf7 Rxb5 19. Nxh8 a5 20. bxa5 Rxa5 21. Ke2 Rf5 22. Rhd1 Nd5 23. g4 hxg4 24. hxg4 Nc3+ 25. Kd3 Nxd1 26. gxf5 Nxe3 27. Kxe3 exf5 28. Kf4 Bc5 29. f3 Bd4 30. Rh1 Kd7 31. Kxf5 Kd6 32. Ke4 c5 33. Nf7+ Ke7 34. Ne5 Ke6 35. Nc4 b5 36. Ne3 Kd7 37. Rh7 Kc7 38. Kd3 Kc6 39. Nc2 Be5 40. Rh5 Kd6 41. Rg5 Bf6 42. Rf5 Kc6 43. f4 Kb6 44. Ke4 Kc6 45. Ne3 Kd6 46. Nd5 Ba1 47. Rg5 Kd7 48. f5 c4 49. Nb4 Ke8 50. Kd5 Kf7 51. Rg6 Bf6 52. Kc6 c3 53. Kxb5 Ke8 54. Nc2 Kd7 55. a4 Kd6 56. a5 Kc7 57. a6 Kb8 58. Kc6 Ka7 59. Kb5

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