#include <stdio.h>

int main() 
{
   int a=0;
   int b=0;
   int 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))
        {
            printf("Equilateral triangle!\n");
        }
        else if((a==b)||(a==c)||(b==c))
        {
            printf("Isosceles triangle!\n");
        }
        else 
        {
            printf("Ordinary triangle!\n");
        }
    }
    else
    {
        printf("Not a triangle!\n");
    }
   }

    return 0;
}