题解 | #三角形判断#

#include <stdio.h>

int main() {
    int a, b, c;
    //判断是否为三角形
    while (scanf("%d %d %d", &a, &b, &c) != EOF) {
        if (a + b <= c || a + c <= b || b + c <= a) {
            printf("Not a triangle!\n");
        } else {
            //判断是否为等边三角形
            if (a == b && b == c && a == c) {
                printf("Equilateral triangle!\n");
            } //判断是否为等腰三角形
            else if ((a == b && b != c && a != c) || (a == c && a != b && c != b) ||
                       (b == c && a != b && c != a)) {
                printf("Isosceles triangle!\n");
            } 
            else {
                printf("Ordinary triangle!\n");
            }
        }
    }
    return 0;
}