spirala

//za zadati broj n formira i stampa matrica sa prvih n*n prirodnih brojeva
//zapisanih u obliku spirale
//1 2 3
//8 9 4
//7 6 5
program spirala;
type
    niz=array[1..20]of integer;
    matrica=array[1..20]of niz;
var
    m,n,i,j,s,k,b,br,l:integer;
    x,y,z:niz;
    a:matrica;

procedure UnosMatrice(var m,n:integer; var a:matrica);
var i,j:integer;
begin
    write('Broj vrsta: ');
    readln(m);
    write('Broj kolona: ');
    readln(n);
    for i:=1 to m do
    begin
        for j:=1 to n do
        begin
        write('A[',i,',',j,']= ');
        readln(A[i,j]);
        writeln;
        end;
    end;
end;


procedure StampaMatrice(m,n:integer; A:matrica);
var i,j:integer;
begin
    writeln;
    for i:=1 to m do
    begin
        for j:=1 to n do
        begin
        write(A[i,j]:4);
        end;

                writeln;
                writeln;
    end;
    writeln;
end;



begin
write('Dimenzija matrice: ');
readln(n);
b:=n div 2;
l:=n-1;
i:=1;
j:=1;
br:=0;
for k:=1 to b do
begin
    i:=k;
    j:=k;
    for s:=1 to l do
    begin
        br:=br+1;
        a[i,j]:=br;
        j:=j+1;
    end;
    for s:=1 to l do
    begin
        br:=br+1;
        a[i,j]:=br;
        i:=i+1;
    end;
    for s:=1 to l do
    begin
        br:=br+1;
        a[i,j]:=br;
        j:=j-1;
    end;
    for s:=1 to l do
    begin
        br:=br+1;
        a[i,j]:=br;
        i:=i-1;
    end;
    l:=l-2;
end;
if(n mod 2=1) then a[b+1,b+1]:=n*n;

StampaMatrice(n,n,a);
readln;
end.