Matritsalar

Matritsa — ro‘yxatlar ro‘yxati: a[i][j] — i-qator, j-ustun.

n, m = map(int, input().split())
a = [list(map(int, input().split())) for _ in range(n)]
grid = [input() for _ in range(n)]     # belgilar jadvali: grid[i][j] — bitta belgi

Andozalar

row_sums = [sum(row) for row in a]
col_sums = [sum(a[i][j] for i in range(n)) for j in range(m)]
diag = sum(a[i][i] for i in range(n))      # bosh diagonal (n × n)
t = [list(col) for col in zip(*a)]         # transponirlash

Qo‘shni kataklar (labirint, «mina» o‘yini):

for di, dj in ((-1, 0), (1, 0), (0, -1), (0, 1)):
    ni, nj = i + di, j + dj
    if 0 <= ni < n and 0 <= nj < m:
        ...

Diqqat

[[0] * m] * n — bitta qatorning n ta nusxasi emas, n ta havolasi: bittasini o‘zgartirsangiz, hammasi o‘zgaradi. To‘g‘risi: [[0] * m for _ in range(n)].