Program a1;
uses crt;
const n=5;
var Mas: array [1..n,1..n] of integer;
      i,j: byte;
      Sum: integer;
Begin
clrscr;
writeln('Please, input your array: ');
for i:=1 to n do
      begin
      for j:=1 to n do read(Mas[i,j]);
      end;
for i:=1 to n do
begin
Sum:=Sum+Mas[i,i];
Sum:=Sum+Mas[i,n-i+1];
Sum:=Sum+Mas[(n div 2)+1,i];
Sum:=Sum+Mas[i,(n div 2)+1];
end;
writeln('Sum= ',Sum);
readln;
End.