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C THIS PROGRAM PLAYS THE GAME OF TRIPLES INTERACTIVELY.
C THE PROGRAM INCLUDES A VARIABLE PLY LOOK-AHEAD WITH ALPHA-BETA
C PRUNING AND A HEURISTIC EVALUATION FUNCTION (SEE EVAL ROUTINE).
C
C THE USER (PLAYER A) IS GIVEN THE CHOICE OF MOVE FOR THE GAME,
C THE SELECTION OF TWO POSSIBLE GAME DIFFICULTY LEVELS,
C AND THE CHOICE OF 23 GAME CONFIGURATIONS.
C THE GAME PROCEEDS WITH A SERIES OF MOVES BY THE PROGRAM AND THE
C USER UNTIL A WIN BY EITHER PLAYER, OR A TERMINATE COMMAND FROM
C THE USER.
C
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C
C INPUT FORMAT:
C   COL 1 - MOVE DIRECTION: S, N, E, W, OR H. OR, REQUEST CODE.
C          (S = SOUTH, N = NORTH, E = EAST, W = WEST, H = HERE)
C   COL 2 - SECOND DIRECTION VECTOR FOR NW, NE, SW, OR SE MOVES,
C           ELSE BLANK.
C
C REQUEST CODES:
C
C T: TO TERMINATE THE GAME.
C R: TO REQUEST A RESHOWING OF THE BOARD WITHOUT A MOVE.
C V: TO REQUEST A LISTING OF THE BOARD VECTORS.
C
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C
C THE OUTPUT OF THIS PROGRAM CONSISTS OF AN IMAGE OF THE BOARD
C AFTER EACH MOVE.  A MESSAGE IS ALSO SENT AT THE END OF THE GAME
C INDICATING THE OUTCOME OF THE GAME.
C
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