#include <stdio.h>

int main() {
    int a, b, c = 0;
    while (scanf("%d %d %d", &a, &b, &c) != EOF) { // 注意 while 处理多个 case
        // 64 位输出请用 printf("%lld") to 
        if((a + b)>c&&(a+c)>b&&(b+c)>a){
            if (a == b && a == 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;
}