def simulate$\_$water$\_$flow$($matrix$)$:

n $=$ len$($matrix$)$

water$\_$level $=$ matrix$[$n $//2][$n $//2]$

while True:

for i in range$($n$)$:

for j in range$($n$)$:

if matrix$[$i$][$j$]==$ water$\_$level:

if i $>0$ and matrix$[$i $-1][$j$]==\text{'}.\text{'}$:

matrix$[$i $-1][$j$]=\text{'}$W$\text{'}$

if i $<$ n $-1$ and matrix$[$i $+1][$j$]==\text{'}.\text{'}$:

matrix$[$i $+1][$j$]=\text{'}$W$\text{'}$

if j $>0$ and matrix$[$i$][$j $-1]==\text{'}.\text{'}$:

matrix$[$i$][$j $-1]=\text{'}$W$\text{'}$

if j $<$ n $-1$ and matrix$[$i$][$j $+1]==\text{'}.\text{'}$:

matrix$[$i$][$j $+1]=\text{'}$W$\text{'}$

if all$($cell $!=\text{'}.\text{'}$ for row in matrix for cell in row$)$:

break

water$\_$level $+=1$

return matrix

# Input reading

n $=$ int$($input$())$

terrain$\_$matrix $=[$list$($map$($int$,$ input$().$split$()))$ for $\_$ in range$($n$)]$

# Call the simulation function

result$\_$matrix $=$ simulate$\_$water$\_$flow$($terrain$\_$matrix$)$

# Print the result

for row in result$\_$matrix:

print$(\text{'}\text{'}.$join$($map$($str$,$ row$)))$