program z711;

const n=3;

Type MyArray=Array[1..n] of integer;

Var A,B :Myarray;

i,j:integer;

begin

Writeln('vv',n,'ch');

For i:=1 to n Do readln(a[i]);

i:=n;

While (i>=1) and (a[i]>0) do dec(i);

if i<1 then writeln('net')else writeln(' est ');

readln;end.