program summa;
uses crt;
const n=7;
var i,j,sum:integer;
a:array[1..100,1..100]of integer;
b,c,d:array[1..100]of integer;
S:string;
begin
clrscr;
{zapolnenie matrichy}
for i:=1 to n do
  begin
   for j:=1 to n do
      begin
        a[i,j]:={random(5)}5;
      end;                         
  end;
{podschet po strokam}
for i:=1 to n do
  begin
   for j:=1 to n do
      begin
        b[i]:=b[i]+a[i,j];
      end;
end;
{podschet po stolbcham}
for j:=1 to n do
  begin
   for i:=1 to n do
      begin
        c[j]:=c[j]+a[i,j];
      end;
 end;
for i:=1 to n-1 do
    begin
      if (b[i]=b[i+1]) and (c[i]=c[i+1]) and (b[1]=c[1]) then
      S:='Yes' else S:='No';
    end;
write(S);readln;
end.