IQ wrote:Proving a win is always 1000 times harder than proving a draw.
Pardon me, Roberto, but that's nonsense.
For both you need just one forced line.
Even more than that, lines to mate are much more often forced than such to draw, in both cases it just depends on the position only of course.
IQ wrote:
50. Bd5 Rc8 51. Qf4 Qg8 52. Bb7 Rce8 53. Qd6 c4
54. a4 c3 55. Bd5 Rd8 56. Qc7 Ke8 57. Qxc3 Qf8 58. Rf4 Re6
59. Bxe6 dxe6 60. a5 Rd7 61. Qc8+ Rd8 62. Qc6+ Rd7 63. Qc3 a6 64. Qc8+ Ke7 65. Qxa6
65...Qb8 66.Ra4 Rd2 67.Qc6 Qa7 68.Qf3 Qc5 69.Ra1 Qd4 70.Ra3 Qb2
and now
71. a6!?
when i was first analysing this I marked this as winning, but now i am not so sure anymore. What is your analysis here?
50. Bd5 Rc8 51. Qf4 Qg8 52. Bb7 Rce8 53. Qd6 c4
54. a4 c3 55. Bd5 Rd8 56. Qc7 Ke8 57. Qxc3 Qf8 58. Rf4 Re6 59. Bxe6 dxe6 60. a5
Rd7 61. Qc8+ Rd8 62. Qc6+ Rd7 63. Qc3 a6 64. Qc8+ Ke7 65. Qxa6
65...Qb8 66. Ra4 Rd2
67. Qc6 Qa7 68. Qf3 Qc5 69. Ra1 Qd4 70. Ra3 Qb2 71. a6
71... Rxf2+ 72. Qxf2 Qxa3 73.
Qa7+ Kf6 74. Qb6 Qd3 75. Qf2+ Ke7 76. Qc5+ Kd7 77. a7 Qa6 78. Kf2 f6 79. Ke3
Qb7 80. Qa3 Qa8 81. Kf2 Kc7 82. g4 Kb6 83. Qe3+ Kb7 84. Qf3+ Kxa7 85. Qe3+ Kb8
86. Qxe6 Qb7 87. Qxf6 Kc7 88. Qf4+ Kc6 89. Qe4+ Kc7 90. Qxb7+ Kxb7
drawn 6MOB
IQ wrote:
Also white can earlier play 70. Re1... how does black defend?
That's why I wanted to play that out move per move, not to let you come along with several moves for the white side at once questioning me which one to chose.
50. Bd5 Rc8 51. Qf4 Qg8 52. Bb7 Rce8 53. Qd6 c4
54. a4 c3 55. Bd5 Rd8 56. Qc7 Ke8 57. Qxc3 Qf8 58. Rf4 Re6 59. Bxe6 dxe6 60. a5
Rd7 61. Qc8+ Rd8 62. Qc6+ Rd7 63. Qc3 a6 64. Qc8+ Ke7 65. Qxa6 Qb8 66. Ra4 Rd2
67. Qc6 Qa7 68. Qf3 Qc5 69. Ra1 Qd4 70. Re1
70...Qa4 71. Qb7+ Rd7 72. Qb6 Rd6 73.
Qb7+ Rd7 74. Qa8 Qb4 75. Ra1 Qb2 76. Re1 Qb4 77. Rc1 Rd5 78. Qc8 Rd8 79. Qa6
Rd5 80. Qc8 Rd8 81. Qa6 Rd5 82. Qb6 Qxb6 83. axb6 Rd7 84. Rb1 Rb7 85. Kf3 Kd7
86. g4 g5 87. Ke4 f6 88. f3 Kc6
Yet you still can go on playing from an "ending" like the one of the second line, as long as you want, but if you make a Backward of such lines, you get an output like this, even just after our 69...Qd4, the last move we are both sure of, aren't we?
[d]8/4kp1p/4p1pP/P7/3q4/5QP1/3r1PK1/R7 w - - 0 1
Analysis by Houdini 6.03 Pro x64-popc:
70.Ra3 Qb2 71.Ra4 Qb5 72.Ra1 Rd3 73.Qe4 Rd2 74.Qf4 Qb7+ 75.Kg1 Qb2 76.Rf1 Qd4 77.Qg5+ Kf8 78.Qb5 Ra2 79.Qb1 Ra3 80.Qb8+ Ke7 81.Rb1 Rd3 82.Qb7+ Kf6 83.Kg2 Qd5+ 84.Qxd5 Rxd5 85.Ra1 Kg5 86.Ra4 f5 87.f4+ Kxh6 88.a6 Rd2+ 89.Kf3 Rd8 90.a7 Ra8 91.Ra6 Kh5 92.Ra3 g5 93.Ra6 h6 94.Ra4 Kg6 95.Ra2 Kf7 96.Ke3 Kg6 97.Ra6 Kf6 98.Ra5 Kg6 99.Ra1
= (0.15) Depth: 37/111 00:16:13 34651MN, tb=57019134
Of course you have to do Backward from more than one line to get such low evals in such a short computing- time, but you as an old analyst do know that anyhow. The 32G hash were already full when coming back to the position of the dia for the last time.
And in this case it was somewhat easier, cause I had 32G hash already stored at 65.Qa6+, where you saw the output of Houdini's too in the posting here:
http://www.talkchess.com/forum/viewtopi ... 11&t=66184
Now, that you started to look at single output- lines more than at reasonable games obviously, I'm sure you are an educated reader of such output- lines and don't take them for reliable for more then the first few plies only. If you want to take some moves from me, stick to one of the two lines given, don't take the output- line, even if I checked it up to 80th move and it seemed ok so far too.
And for our further analysis please decide for one of the two lines to hop in with an alternative white move whereever you want. From there onward of course you can give several moves again, if I'm free to change any of your moves for Black's side then again.
And stick to one more try, as if we'd have a real game, not a Lyudmil Deja Vu.
And If we reach 100 moves without any progress for White, you'll have to go on on your own alone again, Roberto