//Senior-5
//Bob Jones High School
//Contest #1
//Nathan Arce
#include<iostream.h>
int main(void){
    float a,b,c,d,e,f;
    int x=0;
    for(char ch;x<5;x++){
    cin>>a>>ch>>b>>ch>>c>>ch>>d>>ch>>e>>ch>>f;
    if(a+b<=c||a+c<=b||c+b<=a||d+e<=f||d+f<=e||f+e<=d) cout<<"NOT VALID\n";
    else if(d/a==e/b&&e/b==f/c) cout<<"DEF\n";
    else if(d/a==e/c&&e/c==f/b) cout<<"EDF\n";
    else if(d/b==e/a&&e/a==f/c) cout<<"FED\n";
    else if(d/b==e/c&&e/c==f/a) cout<<"FDE\n";
    else if(d/c==e/a&&e/a==f/b) cout<<"EFD\n";
    else if(d/c==e/b&&e/b==f/a) cout<<"DFE\n";
    else cout<<"NONE\n"; }
system("pause");
return 0;}