aa1_practice2

function A = test_proodou1( K, value)

[m,n] = size(K);
while m ~= n
    fprintf('den einai tetragonikos!!! \n')
    K = input('dose neo pinaka: ');
    [m,n] = size(K);
end
    
%A = zeros(n);
for i = 1:n
    for j = 1:n
        if i + j <= value
            K(i,j) = 0;
        end
    end
end
A=K;
end