题解 | #三角形判断#

int main() {
    int a, b, c;
    while (scanf("%d %d %d", &a, &b, &c) != EOF) {
        if (a > 0 && b > 0 && c > 0 && (a + b) > c && (a + c) >b && (b + c) >a) {
            //三边大于0且两边之和大于第三

            if (a == b && b == c && 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");
        }
    }
}