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Advent of Code 2021 Python Solution: Day 13

Today's challenge was fun to do and it was not that hard as well.


import numpy as np
data1, data = get_data(day=13)

dots = [list(map(int, f.split(","))) for f in data[:data.index("")]]
folds = data[data.index("")+1:]
folds = [f.split("along ")[1].split("=") for f in folds]
folds = [(f[0], int(f[1])) for f in folds]

dots = np.array(dots)
window = np.zeros(dots.max(axis=0)+3)

for c in dots:
    window[c[0], c[1]] = 1
window = window.T

tw = window.copy()
# print(tw)
for f in folds:
    cr,cc = tw.shape
    if axis=="y":
        #fold y axis
        chunk = tw[value+1:-2]
        # print(value-crs,chunk.shape, chunk)
        crs,ccs = chunk.shape
        tw[np.abs(value-crs):value] += chunk[::-1]
        tw = tw[:value]
        tw = np.append(tw, np.zeros((2, tw.shape[1])), axis=0)

        # fold x axis
        chunk = tw[:, value+1:-2]
        crs,ccs = chunk.shape
        print(value-crs,chunk.shape, chunk)
        tw[:, abs(value-ccs):value] += chunk[:,::-1]
        tw = tw[:, :value]
        tw = np.append(tw, np.zeros((tw.shape[0], 2)), axis=1)
    print(f"Dots: {np.sum(tw>0)}")

print(np.array2string(tw>0, separator='',
    formatter = {'bool':lambda x: ' █'[x]}))
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My answer was:

[[ ██     ███  ███  ███   ██     ████   ]
 [                           ]
 [   ████                      ]
 [████    ███  ███  ███  ████          ]
 [                             ]
 [                     ██  ████   ]
 [                                          ]
 [                                          ]]
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How to write a kickass README

Arguably the single most important piece of documentation for any open source project is the README. A good README not only informs people what the project does and who it is for but also how they use and contribute to it.

If you write a README without sufficient explanation of what your project does or how people can use it then it pretty much defeats the purpose of being open source as other developers are less likely to engage with or contribute towards it.