#include <stdio.h>

int main() {
    int a, b, c;
    while (scanf("%d %d %d", &a, &b, &c) != EOF) {
        if (a == b && b == c)
            printf("Equilateral triangle!\n");
        else if (a + b > c && b + c > a && a + c > b) {
            if (a == b || b == c || a == c)
                printf("Isosceles triangle!\n");
            else
                printf("Ordinary triangle!\n");
        } else
            printf("Not a triangle!\n");
    }
    return 0;
}