How to solve the Sort and Combine problem

[cloudytechi147]

I am attempting to combine four lists of one row and two columns, such as line_parts=[[2, 1], [2, 0], [1, 2], [5, 2]], to create a list of one row and five columns, such as all_lines=[[5, 2, 1, 2, 0]]. However, the list of four 1-line 2-column lists is written as line_parts=[[2, 1], [2, 0], [1, 2], [5, 2]], but I would like to make it a 1-line 5-column list even if it is [[2, 1], [1, 2], [2, 0], [5, 2]], [[2, 1], [1, 2], [5, 2], [2, 0]], [[1, 2], [5, 2], [2, 0], [2, 1]], etc with pattern programs in c.

Currently, I am able to create a one-row, five-column list for [[5, 2, 1, 2, 0]] from line_parts=[[2, 1], [2, 0], [1, 2], [5, 2]].

line_parts=[[2, 1], [2, 0], [1, 2], [5, 2]]

lines = []
for i,j in line_parts:
    if i == 5:
        path = [ int(i), j ]
        line_parts.remove(line_parts[line_parts.index([i,j])])
        while len(path) != len(line_parts) + 2:
            if path[-1] == 0:
                del path[-1]
                line_parts.insert(len(line_parts),line_parts[0])
                line_parts.remove(line_parts[0])
            else:
                line_parts.insert(len(line_parts),line_parts[0])
                line_parts.remove(line_parts[0])
                while path[-1] != 0:
                    line_parts.insert(len(line_parts),line_parts[0])
                    line_parts.remove(line_parts[0])
                    for m, n in line_parts:
                        if m == path[-1]:
                            path.append(n)
                            break
        lines.append(path)
all_lines=lines

print("all_lines:",all_lines)

The result of running the above program is as follows

all_lines: [[5, 2, 1, 2, 0]]

However, when I change line_parts=[[2, 1], [2, 0], [1, 2], [5, 2]] to line_parts=[[2, 1], [1, 2], [2, 0], [5, 2]], an infinite loop occurs and I don't get a 1-line, 5-column list like [[5, 2, 1, 2, 0]]. I have tried to improve it, but it keeps repeating over and over again that one pattern outputs a one-line, five-column list like [[5, 2, 1, 2, 0]], but another pattern does not work.

Can you please give me some hints or suggestions on how to improve the program so that I can get a one-line, five-column list in all cases, not just [[2, 1], [2, 0], [1, 2], [5, 2]], but [[2, 1], [1, 2], [2, 0], [5, 2]], [[2, 1], [1, 2], [5, 2], [2, 0]], [[1, 2], [5, 2], [2, 0], [2, 1]], etc.?

 

[mikrom]

Hi cloudytechi147,

Could you please explain the rules, how from this given list

line_parts = [[2, 1], [2, 0], [1, 2], [5, 2]]​

this resulting list

all_lines = [[5, 2, 1, 2, 0]]​

should be created?