#include <stdio.h> int main() { int a = 0;//初始化 int b = 0; int c = 0; while (scanf("%d %d %d", &a, &b, &c) != EOF)//多组输入 { //三角形的判断条件 if (a + b > c && a + c > b && b + c > a && a - b < c && a - c < b && b - c < a) { //等腰三角形 if ((a == b && a != c) || (a == c && a != b) || (b == c && b != a)) { printf("Isosceles triangle!\n"); } //等边三角形 else if (a == b && b == c) { printf("Equilateral triangle!\n"); } //其余三角形 else { printf("Ordinary triangle!\n"); } } else { printf("Not a triangle!\n"); } } return 0; }