LUMEN

https://www.codingame.com/training/easy/lumen

Practice Loops and 2D array with the exercise "Lumen"

import sys
import math
 
n = int(input())
l = int(input())
line = [[''for i in range(n)]for j in range(n)]
for i in range(n):
    line[i] = input().split()
 
for i in range(n):
    for j in range(n):
        if line[i][j]=='C':
            for x in range(-(l-1), l):
                for y in range(-(l-1), l):
                    if i+x<0 or i+x>=n or j+y<0 or j+y>=n or line[i+x][j+y]=='C':
                        continue
                    line[i+x][j+y] = 'O'
 
count=0
for i in range(n):
    for j in range(n):
        if line[i][j]=='X':
            count = count+1
print(count)