#include<stdio.h>
int main(){
    int a,b,c;
    while((scanf("%d%d%d",&a,&b,&c)!=EOF && (a>0&&b>0&&c>0&&a<1000&&b<1000&&c<1000))){
        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;
}