#include <stdio.h>

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