Packages
fixpoint
0.21.4
0.22.3
0.22.2
0.22.1
0.21.5
0.21.4
0.21.3
0.21.2
0.21.1
0.21.0
0.20.6
0.20.5
0.20.4
0.20.3
0.20.2
0.20.1
0.19.5
0.19.4
0.19.3
0.19.2
0.19.1
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0.18.1
0.17.6
0.17.5
0.17.4
0.17.3
0.17.2
0.17.1
0.16.5
0.16.4
0.16.3
0.16.2
0.16.1
0.16.0
0.15.6
0.15.5
0.15.4
0.15.3
0.15.2
0.15.1
0.15.0
0.14.9
0.14.8
0.14.7
0.14.6
0.14.5
0.14.4
0.14.3
0.14.2
0.14.1
0.13.5
0.13.4
0.13.2
0.13.1
0.12.9
0.12.8
0.12.7
0.12.6
0.12.5
0.12.4
0.12.2
0.12.1
0.11.8
0.11.7
0.11.6
0.11.5
0.11.4
0.11.3
0.11.2
0.11.1
0.10.7
0.10.6
0.10.5
0.10.4
0.10.3
0.10.2
0.10.1
0.9.12
0.9.11
0.9.10
0.9.9
0.9.8
0.9.7
0.9.6
0.9.5
0.9.4
0.9.3
0.9.2
0.9.1
0.9.0
0.8.52
0.8.51
0.8.50
0.8.49
0.8.48
0.8.46
0.8.44
0.8.43
0.8.42
0.8.41
0.8.40
0.8.39
0.8.38
0.8.37
0.8.36
0.8.35
0.8.34
0.8.33
0.8.32
0.8.31
0.8.30
0.8.29
0.8.28
0.8.27
0.8.26
0.8.25
0.8.24
0.8.23
0.8.22
0.8.21
0.8.20
0.8.19
0.8.18
0.8.17
0.8.16
0.8.15
0.8.14
0.8.13
0.8.12
0.8.11
0.8.10
0.8.9
0.8.8
0.8.7
0.8.6
0.8.5
0.8.4
0.8.3
0.8.2
0.8.1
0.8.0
0.7.10
0.7.9
0.7.8
0.7.7
0.7.6
0.7.5
0.7.4
0.7.3
0.7.2
0.7.1
0.7.0
0.6.5
0.6.4
0.6.3
0.6.2
0.6.1
0.6.0
0.5.12
0.5.11
0.5.10
0.5.9
0.5.8
0.5.7
0.5.6
0.5.5
0.5.4
0.5.3
0.5.2
0.5.1
0.5.0
0.4.3
0.4.2
0.4.1
0.4.0
0.3.6
0.3.5
0.3.4
0.3.3
0.3.2
0.3.1
0.3.0
0.2.3
0.2.2
0.2.1
0.1.3
0.1.2
0.1.1
0.1.0
Constraint Programming Solver
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data/bin_packing/bin_packing/bin_packing.hxm
use io;
/* Read instance data */
function input() {
local usage = "Usage: hexaly bin_packing.hxm "
+ "inFileName=inputFile [solFileName=outputFile] [hxTimeLimit=timeLimit]";
if (inFileName == nil) throw usage;
local inFile = io.openRead(inFileName);
nbItems = inFile.readInt();
binCapacity = inFile.readInt();
itemWeights[i in 0...nbItems] = inFile.readInt();
nbMinBins = ceil(sum[i in 0...nbItems](itemWeights[i]) / binCapacity);
nbMaxBins = min(nbItems, 2 * nbMinBins);
}
/* Declare the optimization model */
function model() {
// Set decisions: bins[k] represents the items in bin k
bins[k in 0...nbMaxBins] <- set(nbItems);
// Each item must be in one bin and one bin only
constraint partition[k in 0...nbMaxBins](bins[k]);
for [k in 0...nbMaxBins] {
// Weight constraint for each bin
binWeights[k] <- sum(bins[k], i => itemWeights[i]);
constraint binWeights[k] <= binCapacity;
// Bin k is used if at least one item is in it
binsUsed[k] <- (count(bins[k]) > 0);
}
// Count the used bins
totalBinsUsed <- sum[k in 0...nbMaxBins](binsUsed[k]);
// Minimize the number of used bins
minimize totalBinsUsed;
}
/* Parametrize the solver */
function param() {
if (hxTimeLimit == nil) hxTimeLimit = 5;
// Stop the search if the lower threshold is reached
hxObjectiveThreshold = nbMinBins;
}
/* Write the solution in a file */
function output() {
if (solFileName == nil) return;
local solFile = io.openWrite(solFileName);
for [k in 0...nbMaxBins] {
if (bins[k].value.count() == 0) continue;
solFile.print("Bin weight: ", binWeights[k].value, " | Items: ");
for [e in bins[k].value]
solFile.print(e + " ");
solFile.println();
}
}