#include <stdio.h>

int main() {
    int a, b, c;
    while (scanf("%d %d %d", &a, &b, &c) != EOF) { 
       if(a+b>c&&a+c>b&&b+c>a){
          if(a==b&&b==c){
            printf("Equilateral triangle!\n");
          }
          else if((a==b&&b!=c)||(a==c&&c!=b)||(b==c&&c!=a)){
            printf("Isosceles triangle!\n");
          }
          else{
            printf("Ordinary triangle!\n");
          }
       }
       else{
        printf("Not a triangle!\n");
       }
       
    }
    return 0;
}