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/* PENTOMINO, a geometric placement puzzle */
/* Written in GNU MathProg by Andrew Makhorin <mao@gnu.org> */
/* A pentomino is a plane geometric figure by joining five equal squares edge to edge. It is a polyomino with five cells. Pentominoes were defined by Prof. Solomon W. Golomb in his book "Polyominoes: Puzzles, Patterns, Problems, and Packings."
There are twelve pentominoes, not counting rotations and reflections as distinct:
+---+ | | +---+ +---+ +---+ | | | | | | +---+---+ +---+ +---+ +---+ | | | | | | | | | +---+---+---+ +---+ +---+ +---+---+ | | | | | | | | | | +---+---+ +---+ +---+---+ +---+---+ | | | | | | | | | +---+ +---+ +---+---+ +---+ F I L N
+---+---+ +---+---+---+ +---+ | | | | | | | | | +---+---+ +---+---+---+ +---+ +---+ +---+ | | | | | | | | | | | +---+---+ +---+ +---+---+---+ +---+---+---+ | | | | | | | | | | | | +---+ +---+ +---+---+---+ +---+---+---+ P T U V
+---+ | | +---+ +---+ +---+---+ +---+---+ | | | | | | | | | | +---+---+ +---+---+---+ +---+---+ +---+---+ | | | | | | | | | | | +---+---+---+ +---+---+---+ +---+ +---+---+ | | | | | | | | | | +---+---+ +---+ +---+ +---+---+ W X Y Z
A classic pentomino puzzle is to tile a given outline, i.e. cover it without overlap and without gaps. Each of 12 pentominoes has an area of 5 unit squares, so the outline must have area of 60 units. Note that it is allowed to rotate and reflect the pentominoes.
(From Wikipedia, the free encyclopedia.) */
set A; check card(A) = 12; /* basic set of pentominoes */
set B{a in A}; /* B[a] is a set of distinct versions of pentomino a obtained by its rotations and reflections */
set C := setof{a in A, b in B[a]} b; check card(C) = 63; /* set of distinct versions of all pentominoes */
set D{c in C}, within {0..4} cross {0..4}; /* D[c] is a set of squares (i,j), relative to (0,0), that constitute a distinct version of pentomino c */
param m, default 6; /* number of rows in the outline */
param n, default 10; /* number of columns in the outline */
set R, default {1..m} cross {1..n}; /* set of squares (i,j), relative to (1,1), of the outline to be tiled with the pentominoes */
check card(R) = 60; /* the outline must have exactly 60 squares */
set S := setof{c in C, i in 1..m, j in 1..n: forall{(ii,jj) in D[c]} ((i+ii,j+jj) in R)} (c,i,j); /* set of all possible placements, where triplet (c,i,j) means that the base square (0,0) of a distinct version of pentomino c is placed at square (i,j) of the outline */
var x{(c,i,j) in S}, binary; /* x[c,i,j] = 1 means that placement (c,i,j) is used in the tiling */
s.t. use{a in A}: sum{(c,i,j) in S: substr(c,1,1) = a} x[c,i,j] = 1; /* every pentomino must be used exactly once */
s.t. cov{(i,j) in R}: sum{(c,ii,jj) in S: (i-ii, j-jj) in D[c]} x[c,ii,jj] = 1; /* every square of the outline must be covered exactly once */
/* this is a feasibility problem, so no objective is needed */
solve;
for {i in 1..m} { for {j in 1..n} { for {0..0: (i,j) in R} { for {(c,ii,jj) in S: (i-ii,j-jj) in D[c] and x[c,ii,jj]} printf " %s", substr(c,1,1); } for {0..0: (i,j) not in R} printf " ."; } printf "\n"; }
data;
/* These data correspond to a puzzle from the book "Pentominoes" by Jon Millington */
param m := 8;
param n := 15;
set R : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 := 1 - - - - - - - + - - - - - - - 2 - - - - - - + + + - - - - - - 3 - - - - - + + + + + - - - - - 4 - - - - + + + - + + + - - - - 5 - - - + + + + - + + + + - - - 6 - - + + + + + - + + + + + - - 7 - + + + + + + - + + + + + + - 8 + + + + + + + + + + + + + + + ;
/* DO NOT CHANGE ANY DATA BELOW! */
set A := F, I, L, N, P, T, U, V, W, X, Y, Z;
set B[F] := F1, F2, F3, F4, F5, F6, F7, F8; set B[I] := I1, I2; set B[L] := L1, L2, L3, L4, L5, L6, L7, L8; set B[N] := N1, N2, N3, N4, N5, N6, N7, N8; set B[P] := P1, P2, P3, P4, P5, P6, P7, P8; set B[T] := T1, T2, T3, T4; set B[U] := U1, U2, U3, U4; set B[V] := V1, V2, V3, V4; set B[W] := W1, W2, W3, W4; set B[X] := X; set B[Y] := Y1, Y2, Y3, Y4, Y5, Y6, Y7, Y8; set B[Z] := Z1, Z2, Z3, Z4;
set D[F1] : 0 1 2 := 0 - + + 1 + + - 2 - + - ;
set D[F2] : 0 1 2 := 0 - + - 1 + + + 2 - - + ;
set D[F3] : 0 1 2 := 0 - + - 1 - + + 2 + + - ;
set D[F4] : 0 1 2 := 0 + - - 1 + + + 2 - + - ;
set D[F5] : 0 1 2 := 0 + + - 1 - + + 2 - + - ;
set D[F6] : 0 1 2 := 0 - - + 1 + + + 2 - + - ;
set D[F7] : 0 1 2 := 0 - + - 1 + + - 2 - + + ;
set D[F8] : 0 1 2 := 0 - + - 1 + + + 2 + - - ;
set D[I1] : 0 := 0 + 1 + 2 + 3 + 4 + ;
set D[I2] : 0 1 2 3 4 := 0 + + + + + ;
set D[L1] : 0 1 := 0 + - 1 + - 2 + - 3 + + ;
set D[L2] : 0 1 2 3 := 0 + + + + 1 + - - - ;
set D[L3] : 0 1 := 0 + + 1 - + 2 - + 3 - + ;
set D[L4] : 0 1 2 3 := 0 - - - + 1 + + + + ;
set D[L5] : 0 1 := 0 - + 1 - + 2 - + 3 + + ;
set D[L6] : 0 1 2 3 := 0 + - - - 1 + + + + ;
set D[L7] : 0 1 := 0 + + 1 + - 2 + - 3 + - ;
set D[L8] : 0 1 2 3 := 0 + + + + 1 - - - + ;
set D[N1] : 0 1 := 0 + - 1 + - 2 + + 3 - + ;
set D[N2] : 0 1 2 3 := 0 - + + + 1 + + - - ;
set D[N3] : 0 1 := 0 + - 1 + + 2 - + 3 - + ;
set D[N4] : 0 1 2 3 := 0 - - + + 1 + + + - ;
set D[N5] : 0 1 := 0 - + 1 - + 2 + + 3 + - ;
set D[N6] : 0 1 2 3 := 0 + + - - 1 - + + + ;
set D[N7] : 0 1 := 0 - + 1 + + 2 + - 3 + - ;
set D[N8] : 0 1 2 3 := 0 + + + - 1 - - + + ;
set D[P1] : 0 1 := 0 + + 1 + + 2 + - ;
set D[P2] : 0 1 2 := 0 + + + 1 - + + ;
set D[P3] : 0 1 := 0 - + 1 + + 2 + + ;
set D[P4] : 0 1 2 := 0 + + - 1 + + + ;
set D[P5] : 0 1 := 0 + + 1 + + 2 - + ;
set D[P6] : 0 1 2 := 0 - + + 1 + + + ;
set D[P7] : 0 1 := 0 + - 1 + + 2 + + ;
set D[P8] : 0 1 2 := 0 + + + 1 + + - ;
set D[T1] : 0 1 2 := 0 + + + 1 - + - 2 - + - ;
set D[T2] : 0 1 2 := 0 - - + 1 + + + 2 - - + ;
set D[T3] : 0 1 2 := 0 - + - 1 - + - 2 + + + ;
set D[T4] : 0 1 2 := 0 + - - 1 + + + 2 + - - ;
set D[U1] : 0 1 2 := 0 + - + 1 + + + ;
set D[U2] : 0 1 := 0 + + 1 + - 2 + + ;
set D[U3] : 0 1 2 := 0 + + + 1 + - + ;
set D[U4] : 0 1 := 0 + + 1 - + 2 + + ;
set D[V1] : 0 1 2 := 0 - - + 1 - - + 2 + + + ;
set D[V2] : 0 1 2 := 0 + - - 1 + - - 2 + + + ;
set D[V3] : 0 1 2 := 0 + + + 1 + - - 2 + - - ;
set D[V4] : 0 1 2 := 0 + + + 1 - - + 2 - - + ;
set D[W1] : 0 1 2 := 0 - - + 1 - + + 2 + + - ;
set D[W2] : 0 1 2 := 0 + - - 1 + + - 2 - + + ;
set D[W3] : 0 1 2 := 0 - + + 1 + + - 2 + - - ;
set D[W4] : 0 1 2 := 0 + + - 1 - + + 2 - - + ;
set D[X] : 0 1 2 := 0 - + - 1 + + + 2 - + - ;
set D[Y1] : 0 1 := 0 + - 1 + - 2 + + 3 + - ;
set D[Y2] : 0 1 2 3 := 0 + + + + 1 - + - - ;
set D[Y3] : 0 1 := 0 - + 1 + + 2 - + 3 - + ;
set D[Y4] : 0 1 2 3 := 0 - - + - 1 + + + + ;
set D[Y5] : 0 1 := 0 - + 1 - + 2 + + 3 - + ;
set D[Y6] : 0 1 2 3 := 0 - + - - 1 + + + + ;
set D[Y7] : 0 1 := 0 + - 1 + + 2 + - 3 + - ;
set D[Y8] : 0 1 2 3 := 0 + + + + 1 - - + - ;
set D[Z1] : 0 1 2 := 0 - + + 1 - + - 2 + + - ;
set D[Z2] : 0 1 2 := 0 + - - 1 + + + 2 - - + ;
set D[Z3] : 0 1 2 := 0 + + - 1 - + - 2 - + + ;
set D[Z4] : 0 1 2 := 0 - - + 1 + + + 2 + - - ;
end;
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