#include <stdio.h>

int main() { double x = 0; double z = 0; double y = 0;

while (scanf("%lf %lf %lf", &x, &y, &z) != EOF)
{
    if (x+y>z && x==y && y==z)
        printf("Equilateral triangle!\n");
    else if(x+y>z && (x==y || y==z || x==z))
        printf("Isosceles triangle!\n");
    else if (x+y>z)
        printf("Ordinary triangle!\n");
    else
        printf("Not a triangle!\n");
}
return 0;

}