6

我正在尝试将数独作为家庭作业的约束满足问题来解决。我已经为特定行中的所有元素以及列构建了约束。我正在尝试为不同的子区域中的元素构建约束，但遇到了一些麻烦。

我当前算法背后的总体思路是将子区域中的所有变量（例如 9x9 网格的 3x3 框）添加到列表中，然后排列该列表中的所有值以在每个变量之间构造 NotEqualConstraints . 下面的代码适用于 NxN 网格的第一个子区域，但我不确定应该如何更改它以遍历整个网格的其余部分。

int incSize = (int)Math.sqrt(svars.length);

ArrayList<Variable> subBox = new ArrayList<Variable>();

for (int ind = 0; ind < incSize; ind++) {
for (int ind2 = 0; ind2 < incSize; ind2++) {
    subBox.add(svars[ind][ind2]);
    }
}

for (int i = 0; i < subBox.size(); i++) {
for (int j = i + 1; j < subBox.size(); j++) {
   NotEqualConstraint row = new NotEqualConstraint(subBox.get(i), subBox.get(j));
   constraints.add(row);
   }
}

任何人都可以指导我如何修改代码以命中每个子区域而不仅仅是左上角的正确方向吗？

编辑：我也愿意尝试任何有效的算法，没有必要将所有值添加到每个子区域的 ArrayList 中。如果您看到更好的方法，请分享见解

4

4 回答 4

3

对于那些感兴趣的人，这是我想出的工作解决方案：

for (int ofs = 0; ofs < svars.length; ofs++) {
    int col = (ofs % incSize) * incSize;
    int row = ((int)(ofs / incSize)) * incSize;

    ArrayList<Variable> subBox = new ArrayList<Variable>();
    for (int ind = row; ind < row+incSize; ind++) {
        for (int ind2 = col; ind2 < col+incSize; ind2++) {
            subBox.add(svars[ind][ind2]);
        }
    }
    for (int i = 0; i < subBox.size(); i++) {
            for (int j = i + 1; j < subBox.size(); j++) {
               NotEqualConstraint c = new NotEqualConstraint(subBox.get(i), subBox.get(j));
               constraints.add(c);
            }
    }   
}
于 2011-10-14T01:24:13.317 回答
1

我不完全确定你想要做什么，但下面的算法应该给你你需要的每一个值。您可以忽略和/或删除不需要的值。您可能可以在拥有所有数字的位置适当地填充所有数组。

我用的词：

  • 方格：放一个数字的一​​个方格。
  • 子区域：一组正方形，经典数独中的 3x3 网格。
  • 拼图：整个东西，3x3 子区域和 9x9 方块。

代码：

//You should have these values at this point:
int subRegionWidth = something; //amount of horizontal squares in a subregion
int subRegionHeight = something; //amount of vertical squares in a subregion
int amountOfHorizontalSubRegions = something; //amount of subRegion columns next to each other
int amountOfVerticalSubRegions = something; //amount of subregion rows on top of each other

//Doesn't change, so calculated once in advance:
int squaresPerPuzzleRow = subRegionWidth*amountOfHorizontalSubRegions;

//Variables to use inside the loop:
int subRegionIndex = 0;
int squareColumnInPuzzle;
int squareRowInPuzzle;
int squareIndexInPuzzle;
int squareIndexInSubRegion;

for(int subRegionRow=0; subRegionRow<amountOfVerticalSubRegions;subRegionRow++)
{
    for(int subRegionColumn=0; subRegionColumn<amountOfHorizontalSubRegions;subRegionColumn++)
    {
        for(int squareRowInRegion=0; squareRowInRegion<subRegionHeight; squareRowInRegion++)
        {
            for(int squareColumnInRegion=0; squareColumnInRegion<subRegionWidth; squareColumnInRegion++)
            {
                squareColumnInPuzzle = subRegionColumn*subRegionWidth + squareColumnInRegion;
                squareRowInPuzzle = subRegionRow*subRegionHeight + squareRowInRegion;
                squareIndexInPuzzle = squareRowInPuzzle*squaresPerPuzzleRow + squareColumnInPuzzle;
                squareIndexInSubRegion = squareRowInRegion*subRegionWidth + squareColumnInRegion;

                //You now have all the information of a square:

                //The subregion's row (subRegionRow)
                //The subregion's column (subRegionColumn)
                //The subregion's index (subRegionIndex)
                //The square's row within the puzzle (squareRowInPuzzle)
                //The square's column within the puzzle (squareColumnInPuzzle)
                //The square's index within the puzzle (squareIndexInPuzzle)
                //The square's row within the subregion (squareRowInSubRegion)
                //The square's column within the subregion (squareColumnInSubRegion)
                //The square's index within the subregion (squareIndexInSubRegion)

                //You'll get this once for all squares, add the code to do something with it here.
            }
        }
        subRegionIndex++;
    }
}

如果您只需要每个子区域的左上角方块，只需删除内部的两个循环：

for(int subRegionRow=0; subRegionRow<amountOfVerticalSubRegions;subRegionRow++)
{
    for(int subRegionColumn=0; subRegionColumn<amountOfHorizontalSubRegions;subRegionColumn++)
    {
        squareColumnInPuzzle = subRegionColumn*subRegionWidth;
        squareRowInPuzzle = subRegionRow*subRegionHeight;
        squareIndexInPuzzle = squareRowInPuzzle*squaresPerPuzzleRow + squareColumnInPuzzle;

        //You now have all the information of a top left square:

        //The subregion's row (subRegionRow)
        //The subregion's column (subRegionColumn)
        //The subregion's index (subRegionIndex)
        //The square's row within the puzzle (squareRowInPuzzle)
        //The square's column within the puzzle (squareColumnInPuzzle)
        //The square's index within the puzzle (squareIndexInPuzzle)
        //The square's row within the subregion (always 0)
        //The square's column within the subregion (always 0)
        //The square's index within the subregion (always 0)

        //You'll get this once for all squares, add the code to do something with it here.

        subRegionIndex++;
    }
}
于 2011-10-20T10:42:26.770 回答
0 
for (int start1 = start1; start1 < svars.length/incSize; start1 ++) {
    for (int start2 = start2; start2 < svars.length/incSize; start2++) {//iterate through all subsets
        ArrayList<Variable> subBox = new ArrayList<Variable>();

        for (int ind = start1*incSize; ind < incSize; ind++) {
            for (int ind2 = start2*incSize; ind2 < incSize; ind2++) {
                 subBox.add(svars[ind][ind2]);
            }
        }

       for (int i = 0; i < subBox.size(); i++) {
        for (int j = i + 1; j < subBox.size(); j++) {
           NotEqualConstraint row = new NotEqualConstraint(subBox.get(i), subBox.get(j));
           constraints.add(row);
           }
        }
    }
}
于 2011-10-09T22:23:25.733 回答
-2

我不完全理解您要做什么，但是如果您要解决难题，则只需要一个递归方法，该方法将输入数字直到填满所有网格并且难题有效。那是我对 futoshiki 的解决方案解谜者（类似于数独）

于 2011-10-11T17:43:59.843 回答