#include<stdio.h>
 int main(){
    int a = 0;
    int b = 0;
    int c = 0;
    while(~scanf("%d%d%d",&a,&b,&c))
    {
        //判断是否为三角形
        if((a+b>c)&&(a+c>b)&&(b+c>a))
        {
            if(a==b & b==c)
                printf("Equilateral triangle!\n");
            else if((a==b &&a!=c) || (a==c && a!=b) || (b==c &&b!=a))
                printf("Isosceles triangle!\n");
            else
                printf("Ordinary triangle!\n");
        }
        else
        {
            printf("Not a triangle!\n");
        }
    }
    return 0;
 }