#include <stdio.h>

int main() {
    int a,b,c;
    scanf("%d %d %d",&a,&b,&c);
    if  (a + b <= c || a + c <= b || b + c <= a){
        printf("Not a triangle!");
        return 0;
        }/*先判断是不是一个三角形,如果是,再判读是什么类型的三角形*/
    else if (a == b && b== c)
        printf("Equilateral triangle!");
    else if (a == b || a == c || b == c)
        printf("Isosceles triangle!");
    else
        printf("Ordinary triangle!");
    return 0;
}