rograff3.pas

This ar the basic programs that i did in highschool. From very simple to medium programs. From array

var a:array[1..50,1..50] of integer;
    n,i,j,k:integer;
    f:text;
    ok:boolean;
begin
assign(f,'graf.txt');
reset(f);
readln(f,n);
while not eof(f) do begin
                    readln(f,i,j);
                    a[i,j]:=1;
                    end;
close(f);
for k:=1 to n do
  for i:=1 to n do
    for j:=1 to n do
      if (a[i,k]=1) and (a[k,j]=0) then a[i,j]:=1;
ok:=true;
for i:=1 to n do
   for j:=1 to n do
      if (i<>j) and (a[i,j]=0) then ok:=false;
{for i:=1 to n-1 do
 for j:=i+1 to n do
    if a[i,j]=0 then ok:=false;   }
if ok then writeln('graf conex ')
      else writeln('graful nu e conex');
readln;
end.

if ok then write('graf conex')
      else write('graful nu e conex');
readln;
end.