题解 | #三角形判断#

#include<stdio.h>
int main() {
    int a, b, c;
    while (scanf("%d %d %d", &a, &b, &c) != EOF ) {
        //三角形三边的关系：两边之和大于第三边,两边之差小于第三边。
        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;
}