aoc11.jl

# ---
# jupyter:
#   jupytext:
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#       extension: .jl
#       format_name: percent
#       format_version: '1.3'
#       jupytext_version: 1.7.1
#   kernelspec:
#     display_name: Julia 1.5.2
#     language: julia
#     name: julia-1.5
# ---

# %%
ex1 = "L.LL.LL.LL
LLLLLLL.LL
L.L.L..L..
LLLL.LL.LL
L.LL.LL.LL
L.LLLLL.LL
..L.L.....
LLLLLLLLLL
L.LLLLLL.L
L.LLLLL.LL"
ex1 = split(ex1, '\n');

# %%
input = "LLLLLLL.LLLLLLLLLLLLLLL.LLL.LLLL.LLLLLLL.L.LLLLLLL.LLLLLL.LLLLLLLL.LLLLL..LLLLLLLLLLLLLLLLLL
LLLLLLL.LLLLLL.LLLL.LLL.LLLLLLLLLL.LLLLLLL.LLLLL.L.LLLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL
.LLLLLLLLLLLLLLL.LLLLLL.LLLLLL.LLLLLLLL.LL.LLLLLLL.LLL.LL.LLLLLLLLLLL.LLL..LLLLLLLL.LLLLLLLL
LLLLLLLLLLLLLLL..LLLLLL.LLLLLLLLLLLLL.LLLL.LLLLLLLLLLLL.L.LLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL
LLLLL.L.LLLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLL.LLLLLLL.LLL..LLL.LLLLLL.LLLLLL.LLLL.LLLL.L.LLLLLL
LLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLL.L.LL.LLLL.LLLLLL..LLLLLL.LLLLLLLL..LLLLL.LLLLLLLL..LLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLL.LLLLL.L.LLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLL
.LLLLLL..LLLLLLL.LLLLLL.LLLLL.LLLLLLLLLLLL.L.LLLLLLLLLLLLLLLLLLLLL.LLLLLL.LLLLLLLLLLLLLL.LLL
..LLLL......L.L..L..L..L.....LL..L.....L.....LLL.L.L.LL...L.....L...LL..L......L...LL......L
LL.LLLL.LLLLLLLLL.LLLLL.LLLLL.LLLLLLL.LLLL.LLLLLL..LLLLLL.LLLL.LLL.LLLLLLLLLLLLLLLLLLLLLLLLL
LLLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLLL.LLLLLLLL.LLLLLL..LLLLLLLLLLLLLLLLLLLLLLLL
LLLLLLLLLLLLLLLL.LLLLLL.LLLLL.LLLLLLL.LLLL.LL.LLLLLL.LLLL.LLLLLLLL.LLLLLL..LL.LLLLL.LLLL..L.
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LLLLLLL.L.LLLLLL.LLLLLLLLL.LL.LLLLL.LLLLL..L.LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLL.LL
LLLLLLLLLLLLLLLL.LLLLLLLLL.LL.LLLLLLL.LLLL.LLLLLLL.LLLLLLLLLLLLLL..LLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLL.LLLLLLL..LLLLLLLLLLLL.LLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLL.LL.LLLLLLLLLLLLLLLL.LLLLLLLL
LLLLLLL.LLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLLLLL.LLLLLL.L.LLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLLLLLLLLLLL.LLLLL..LLLLLLLLLL.LLL.LLLLLLLLLLLLLL.LLL.LLLLLLLLL.LLLLL.L.LLLL.LLLLLLLLLLL
.L......L.LL.L...L.....L..L..L...LL.L.......L.............LL.L......LL.L...LL.L...L.....LL..
LL.LLLL.LLLLLLLLLLLLLLL.LLLLL.LLLLLLLLL.LLLLLLLLLL.LLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLL
LLLLL.L.L.LLLLLLLLL.LLLLLLLLLLLLL.LL.LLLLLLLLLLLLL.LLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLL
LLLL.LL.LL.LLLLL.LLLL.L.LLLLL.LLLLLLLLLL.LLLLLLLLL..L.LLLLLLLLLLL.L.LLLLL.LLLLLLLLLLLLLLLL.L
LLLLLLL.LLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLLLLLLLLLL.LLLLLL.LLLLLLLL.LLLLLL.LLLLLLLLL.LLLLLL.L
.......LL...L.......LL...L.......LLL......L..L...L...L.....LL..L.L......L.LL.....LL.....L...
LLLLLLLLLLLLLLLL.LLLLLL.LLLLL.LLLL.LL.LLLL.LLLLLLL.LLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLLL
LLLLLLL.LLLLLLLLLLLLLL..LLLLLLLLLLLLL.LLLL.LL.LLLL.LLLLLLLLLLLLLLL.LLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLLLLL.LLLLLL.L.LLL.L.LLL.LLL.LLLLLLLL.LLLLLLL.LLLLLLLLLLLLLLL.LLLLLL.LLLLLLLLLLLLLLLLLL
L.LLLLLLL.LLLLLL.LLLLLLL.LLLLLLLLLLLL.LLLLLLLLL.LLLLLLL.LLLLLLLLL..LLLLLL.LLLLLLLLL.LLLLLLLL
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LLLLL.L.LLLLLLLL.LLLLLLLLLL.L.LLL.LLL.LLLL.LLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLL.LLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLL.LLLLL.LLLLL.L.LLLLLLLLLLLL.LLLLLL.LLLLLLLL.LLLLLL.LLLLLL.LL.LLL.LLLL
L..LL.........L....L....L..L.LL.....LL.L.LL...L........L...L...L...L.LLL..LL..LLLLL.L.......
LLLLLLL.LLLLLLLLLLLL.LL.LLLLL.LLLLLLL.LLLLLLLLLLLLLLLLL.L.LLLLLLLL.LLLLLL.LLLLLLL.L..LLLLLLL
LLLLLLLL.LLLLLLL.LLLLLL.LLLLL.LLLLLLLLLLLL.LLLLLLL.LLLLLL.LLLLLLLL.LLLLLL.LLLL.L.LL.LLLLLLLL
.LLLLLL.LLLLLL.L.LLLLLL.LLLLL.LLLLLLL.L.LL.LLLLLLLLLLL.LLLLLLLLLLL.LLLLLL.LLLLLLLL..LLLLLLLL
LL.LLLL..LLLLLLL.LLLLLL.LLLLL.LLLLLLLLLLLL.LLLLLL..LLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLL
L..LL..........L......L..L....L..L.L.LL.LLL..L.L.L.LLLL...L..L..L.L.L..LLLL.L.L...L..LL.....
LLLLLLLLLLLLLLLLLLLLLLL.LL.LLLLLLLLLL.LL.L.LLLLLLL.LLLLLL.LLL.LLLLLLLLLLLLLLLLLLLLL.LLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLLLLLLLL.LLLL.LL.LLLLL.LL.LLL.LLLLLLLLLLLLLLL.LLL.LLLLLLLLLLLLL.LLLLLL.
LLLLLL.LLLLLLLLL.LLLLL.LLLLLL.LLLLLLLLLLLLLLLLLLLL.LLLLLL.LLLLLLLL.LLLLLL.LLLLLLL.LLLLLLLLLL
LLLLLLLLLLL.LLLL.LLLLLLLLLLLLLLLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLLLLL.LLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLL.LLLL.LLL.LLLLLL.LLL.L.LLLLLLLLL.LL.LLLLLLLLLLLLLL.LLLLLLLL.LLLLLLLLLLLL.LLL.L.LLLLLL
LLLLLLLLLLLLL.LL.LLLLLL.LLL.L.LLLLLLL.LLLLLLLLLLLL.LLLLLL.LLLL.LLL.LLLLLL.LLLLLL.LLLLLLLLLLL
.L.LLLL.L.LLL.L....L...LL.L.L..LL.L.LLLL.L..L..L.L.LL...LL..L.L.L...LL.L.......LL..LLL......
LLLLL.L..LLLLLLLLLLLLLLLLLLL.LLLLLL.LLLLLL.LL.LLLL.LLLLLL.LLLLLL.L.LLLLLL.LLLLLLLLLLLL.LLLLL
LLLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLLLLL..LLL.LLLLLLL.LLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLL.L.LLLLLL
LLLLLLL.LLLLLLLL.LLLL.L.LLL.LLLLLLLLL.LLLL.LLLLLLL.L..LLL.LLLLLLL..LL.LLL.LLLLLLLLL.LLL.LLL.
LLLLLLL.LLLLLLLL.LLLLLL.L.LLLLLLLLLL..LLLLLLLLLLLL.L.LLLL.LLLLLLLL.LLLLLL.L.LLLL.LL.LLLL.LLL
LLLL.LLLLLLLLLL.LLLLLLL.LLLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLLL.LLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL
LLLLLLL.LLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLLLLL.LLLLLL.LL.LLLLL.LLL.LL.LLLLLLLLLLLLLLLLLL
LL.LLLLLLLLLLLLL.LLLLLLLLLLLL.LLL.LLL.LLLL.LLLLLLLLLLLL.L.LLLLL.LL.LLLLLL.L.L.LLLLLLLLLLLLLL
LLLLLL.LLLLLL.LL.LLLLLLLLL.LLLLLLLLLL.LLLL.LL.LLLLLLLLLLL.LL.LLLLL.LLLLL.LLLLLLLLLL.LLLLLLLL
.LLL.......LL.LL....L..L.....LL.....L..L...LLL....L...L..LLL...L............LLLL.LL.......L.
LLLLL.L.LLLLLLLLLLLLLLLLLLLLL.L.LLLLLLLLLLLLLL.LLLLLLLLLL.LLLLLLLLLLL.LLLLLLLLLL.LL.LLLLLLLL
LLLLLLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLL.LLLL.LLLLLLLLLLLLLL.LLLLLLLL.LLLL.LLLLLLLLLLLLLLLLLLLL
L.LLLLL...LLLLLLLLLLLLL.LLLLLLLLLLLLL..LLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL
LLLLLLLLLLLLLLLL.L.L.LLLLLLLL.LLLLLLL.LLLL.LLLLL.L.LLLLLL.LLLLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL
LLL.LLLLLLLLLLLLLLLLLLL.LLL.LLLLLLLLLL.LLL.LLLLLL..LLLLLL.LLLLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL
L..L.LL...LLL.L...LLL....L.L.L.L.....LL..........LL...L.L.L.LLLL....L.....L....LLL......LLLL
LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLLLL.L.LLLLLL.LLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLL..LLLLLLLLLLLLLL.LLLLLLLLLLLLLL.LLL.LLLLLLL.LLLLLLLLLLLLLLLLLL.LLL.L.L.LL.LLLLLLLLLLL
LLLLLLLLLLLLLLLL.LLLL.L.LLLLL.LLLL.LLLLLLL.LLLLLLLLLLLLLLLLLLLLLLL.L.LLLLLLLL.LLLLLLLLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLL.LLLLL.LLLLLLLLLLLL.LLLLLLL.LLLLLLLLLLLLLLL.LLLLLL.LLLLLLLLL.LLLLLL.L
LLLLLLLL.LLLLLLL.LLLLLLLLLLLL.LLLLLLL.LLLL.LLL.LLL.LLLLLL.LLLLLLLL.LLLLLL.LLL.LLLLL.LLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLL..LLLLLLLLLLLL.LLLL.L..L.LL.LLLLLL.LLLLLLLLLLLLLLLLLLLLLLL.L.LLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLL.LLLLLLLLLLLL..LLLLLLLLLLLL.LLLLLLLLLL.LLLL.LLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLLLLLLLLLLL.LLLLLL.LLLLLLLLLLLLLLLL.L.LLLLLLL.LLLLLL.LLLLLLLL.LLLLLL.LLLLLLLLLLLLLLLLLL
LLLLLL..LLLLLLLL.LLLLLLLLLLLL.LLLLLL..LLLL.LLLL.LL.L.LLLL.LLLL.LLL.LLLLLL.LLLLLLLLLLLL.LLLLL
........LL..LL..L............L..L.L..L....L.......LL...L......L....LLL..L.L......LL..LL.L.L.
LLLLLLL.LLLLLLLL.LLLLLLLLLLLL.LLLLLL..LLLL.LLLLLLL.LLL.LL.LLLLLLLL.LLLLLL.LLLLLLLLL.LLL.LLLL
LLLLLL.LLLLLLLLL.LLLLLL.LLLLL.LLLLLLLLLLLL.LLLLL.LLLLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLL
LLL.LLL.LLLLLLL.LLLLLLL.LLLLL.LLLLLLLLLLL..LLL.LLL.LLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLL.LLLLLLLL.LLLL.L.LLLLL.LL.LLLL.LLLL.L.LLLLL.LL.LLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLL
LLLL.LLLLLLLLLLLLLLLLLL.LLLLLLLLLLLL..LLLL.LLLLLL.LLLLLLL.LLLLLL.LLLLLLLL.LLLLLLL.L.LLLLLLLL
LLLLLLL.LLLLL.LL.LLL.LL.LLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLL.LLLLLLLLLLLLL.LLLLLL.LLLL.LL.LLLLL
LLLLLLLLLL.LLLLLLLLLLLL.LLLLL.LLLLLLL.LLLLLLLLLLLLLLLLLLL.LLLLLLLL.LL.LLLLLLLLLLLLL.LLLLLLLL
LLLL.L.L...L.......L..LL.LL.LL....LL..L.L.L......L...LLL..L.L.L...LLL...L.....L.LLLL........
.LLLLLL.L.LLLLLL.LLLLLLLLLLL..LLLLLLL.LLLL.LLLLLLL.LLLLLL.LLLLL.LLLLLLLLL.LLLL.LLLL.LLLLLLLL
LLLLLLL.LLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLL.LLLLLLL.LLLLLL.LLLLLLLL.LLLLLLLLLLLLLLLL.LLLLLLL.
LLLLLLL.L.LLLLLLLLLLLLL.LLLLL.LLL.LLL.LLLL.LLLLLLL.LLLLLLLLLLLLLLL.LLL.LL.L.LLLLLLLLLLLLLLLL
LLLLLLL.LLLLL.LL.LLLLLL.LLLLLLLLLLLLL.LLLL.LLLLLLLLLLL.LL.LLLLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL
L.LLLLL.LLLLL.LLLLLLLLL.LLLLL..LLLLLL.LLLL.LLLLLLL.L.LLLL.LLLLLLLL.LLLLLL.LLLLLLLLL.LLL.LL..
..L...L.L.......LL.LLL.LLL..L....L..L.L.L..L.L........L...L.LL.L.........LLLLL.L.LL.L...L.LL
LLLLLLL.LLLLL.LL.LLLLLL.LLLL..LLLLL.L.LL.LLLLLL.LL.LLLLLLLLLLLLLLL.LLL.LLLLLLLLLLLLLLLLLLLLL
LLLLLLL.L.LLLLLLLLLLLLL.LLLLL.LL.LLLLLLL.LLLLLLLLL.LLL.LL.LLLLLLLL.LLL.LL.LLLLLLLLL.LLLLLLLL
LLLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLL..L.LLLLLLLLLLLL.LLLLLL.L.LLLLLL.LLLLLL.LLLLLLLLL.LLL.LLLL
.LLLLLL.LL.LL.LLLLLL.L..LLLLLLL.LLLLL.LLLL.LL.LL.L.LL.L.L.LLLLLLLL.LLLLLLLLLLLLLLLL.LLLLLLLL
LLLLLLLLLLLLLLLLLLLLLLL..LLLLLLLL.LLL.LLLLLLLLLLLLLLLLLL..LLLLLLLL.LLLLLL.LLLLLLLLLLLLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLL.LLLLL.LLLLLLLLLLLL.LLLLLLL.LL.LL..LLLLLLLL.LLLLLLLLLLLLLLLL.LLL..LLL
LLLLLLLLL.LL.LLL.LLLLLLLLLLLLLLLLLLLL.LLL..LLLLLLLLLLLLLL.LLLLLLLL.LLLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLL.LLLL.LLLLLLLLLLL.LLLL.LLLLLLLLLL.L.LLLLLLL.LLLLLL.LLLLLLLLLLLLLLLLLLLLLLLLLLLL.LLLLL
LLL......LL...L...L..LL..L..L......L...L.L..L.........L.LL.LL..L..L.L......L..L........L..L.
LL.LLLLLLLLLLLLL.LL.LLLLLLLLLLLLLLLLLLLLLL.LLLLLLL.LLLLLLLLLLLLLLL.LLLLLLLLLLLLL.LLLLLLLLLLL
LLLLLLLLLLLLLL.L.LLLLLLLLLLLL.LL.LLLL..LLL.LLLLLLLLLLLLLLLLLLLLLLL.LLLLLL.LLLLLL.LL.LLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLL.LLLLL.LLLLLLL.LLLLLLLLLL.L.LLLLLL.LLLLLLLL..LLLLL.LLLLLLLLL.LLLLLLLL
LLLLLLL.LLLLLLLL.LLLLLLLLLLLLLLLLLLLL.LLLLLLLLLLLL.LLLLLLLLLLL.LLL.LLLLLL.LL.LLLLLL.LLLLLLLL
LLLLLLLLLLLLLLLL.LLLLLL.LLL.L.LLLLLLL.LLLLLLLLLLLL.LLLLLLLLL.LLL.L.LLLLLL.LLLLLLLLLLLLLLLLLL
LLLLLLL.LLLLL.LL.LL.LLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL..LLLLLLLLLLLLLLLLLLLLLLLL.LLLLLLLL
LLL.LLLLLLLLLLLL.LLLLLLLLLLLL.LLLLLLLLLLLLLLLLLLLL.LLLLLL.LLL.LLLLLLLLLLL.LLLLLLLLL.LLLLLLLL"
input = split(input, '\n');


# %%
function to_array(los)
# los is list of strings
    seats = Array{Char, 2}(undef, length(los), length(los[1]))
    rows = length(los)
    cols = length(los[1])
    for row in 1:rows
        for col in 1:cols
            seats[row, col] = los[row][col]
        end
    end
    return seats
end

# %%
ex1 = to_array(ex1)
input = to_array(input);# doing this because strings are inmutable

# %%
function grid_print(array)
    string = ""
    for r in 1:size(array)[1]
        for c in 1:size(array)[2]
            string = string*array[r, c]
        end
        string = string*'\n'
    end
    print(string)
end

# %%
function find_a_seat(input, verbose = false)
    # one cycle
    output = copy(input)
    num_changes = 0
    rows = size(input)[1]
    cols = size(input)[2]
    for row in 1:rows
        for col in 1:cols
            
            neighbors = 0
            for i in -1:1, j in -1:1
                if i == j == 0
                    continue # skip iter
                elseif row == 1 && (i == -1)
                    continue
                elseif col == 1 && j == -1
                    continue
                elseif col == cols && j == 1
                    continue
                elseif row == rows && i ==1 
                    continue
                end
                
                if input[row+i, col+j] == '#'
                    neighbors +=1
                end
                
            end 

            if neighbors > 3 && input[row, col] == '#'
                output[row, col] = 'L'
                num_changes +=1
            elseif neighbors == 0 && input[row, col] == 'L'
                output[row, col] = '#'
                num_changes +=1
            end
            
        end
    end        
    if verbose 
        grid_print(input) 
        print("\n\n")
        grid_print(output)
        print("\n\n---------------\n\n")
    end
    
    if num_changes == 0
        print("No more changes\n")
        if verbose grid_print(output) end
    end
    
    return output, num_changes
end

# %%
function converge(fun, input; verbose = false)
    output = copy(input)
    num_changes = 1
    while num_changes !=0
        output, num_changes = fun(output, verbose)
    end
    if verbose grid_print(output) end
    length(findall(==('#'), output))
end

# %%
converge(find_a_seat, ex1)

# %%
converge(find_a_seat, input)

# %% [markdown]
# ## Part 2

# %%
function find_a_seat2(input, verbose = false)
    # one cycle
    output = copy(input)
    num_changes = 0
    rows = size(input)[1]
    cols = size(input)[2]
    debug = Array{Int, 2}(undef, rows, cols)
    
    for row in 1:rows
        for col in 1:cols
            neighbors = 0
            for i in -1:1, j in -1:1
                
                if i == j == 0
                    continue # skip iter
                elseif row == 1 && i == -1
                    continue
                elseif row == rows && i ==1 
                    continue
                elseif col == 1 && j == -1
                    continue
                elseif col == cols && j == 1
                    continue
                end
                
                border_or_seat = false
                step = 1
                
                while !border_or_seat
                    
                    if input[row+i*step, col+j*step] == '#'
                        neighbors +=1
                        border_or_seat = true # occupied seat found
                    elseif input[row+i*step, col+j*step] == 'L'
                        border_or_seat = true # empty seat found
                    end
                    
                    if ((row+i*step == 1) && i!=0) ||
                        ((col+j*step == 1) && j!=0) ||
                        ((row+i*step == rows) && i!=0) ||
                        ((col+j*step == cols) && j!=0)
                        border_or_seat = true # border found
                    end
                    
                    step +=1
                    
                end
                
            end 
            
            debug[row, col] = neighbors

            if neighbors > 4 && input[row, col] == '#'
                output[row, col] = 'L'
                num_changes +=1
            elseif neighbors == 0 && input[row, col] == 'L'
                output[row, col] = '#'
                num_changes +=1
            end
            
        end
    end        
    if verbose 
        display(input) 
        print("\n\n")
        display(debug)
        print("\n\n")
        display(output)
        print("\n\n---------------\n\n")
    end
    
    if num_changes == 0
        print("No more changes\n")
        if verbose grid_print(output) end
    end
    
    return output, num_changes
end

# %%
converge(find_a_seat2, ex1)

# %%
converge(find_a_seat2, input)

# %%