#include <stdio.h>

void decideShape(int max, int small_1, int small_2) {
    if (small_1 + small_2 > max) {
        if (small_1 == small_2) {
            if (small_1 == max) {
                printf("Equilateral triangle");
            }
            else {
                printf("Isosceles triangle");
            }
        }
        else {
            printf("Triangle");
        }
    }
    else {
        printf("Not a triangle");
    }
}

int main() {
    int a = 0, b = 0, c = 0;
    scanf("%d %d %d", &a, &b, &c);
    if (a > c) {
        if (a > b) {
            decideShape(a, b, c);
        }
        else {
            decideShape(b, a, c);
        }
    }
    else {
        if (c > b) {
            decideShape(c, a, b);
        }
        else {
            decideShape(b, a, c);
        }
    }
    return 0;
}