1986B - Matrix Stabilization - CodeForces Solution

t = int(input())
for _ in range(t):
    n,m = map(int,input().split())
    arr=[]
    for i in range(n):
        arr.append(list(map(int,input().split())))
    for rI in range(n):
        for cI in  range(m):
            item=arr[rI][cI]
            if rI == 0:
                up=0
            else:
                up=arr[rI-1][cI]
            if rI == n-1:
                down=0
            else:
                down=arr[rI+1][cI]
                
            if cI == 0:
                left=0
            else:
                left=arr[rI][cI-1]
            if cI == m-1:
                right=0
            else:
                right= arr[rI][cI+1]
            if up < item and down < item and left < item and right < item :
                arr[rI][cI]=max(up , down , left, right)
    for row in arr:
        for num in row:
            print(num,end=" ")
        print()