var
a: array [1..100, 1..100] of integer;
i, j, n: integer;
f:boolean;
begin
readln(n);
for i := 1 to n do
for j := 1 to n do
read(a[i, j]);
f:=true;
i:=1;
while (i<=n-1)and(f)do
begin
j:=i+1;
while (j<=n)and(f)do
if a[i,j]=a[j,i] then inc(j)
else f:=false;
inc(i);
end;
if f then writeln('yes')
else writeln('no');
end.
