백준/5073/삼각형과 세 변/C

https://www.acmicpc.net/problem/5073

5073번: 삼각형과 세 변

---

1) c

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#pragma warning(disable:4996)

int a, b, c;
int arr[4];

int compare(const int* a, const int* b) {
	int A = (*(int*)a);
	int B = (*(int*)b);
	if (A < B) { return 1; }
	else if (A == B) { return 0; }
	return -1;
}

void res() {
	if (arr[0]  >= arr[1] + arr[2]) { printf("Invalid\n"); }
	else if (arr[0] == arr[1] && arr[1] == arr[2]) { printf("Equilateral\n"); }
	else if (arr[0] == arr[1] || arr[1] == arr[2]) { printf("Isosceles\n"); }
	else if (arr[0] != arr[1] && arr[1] != arr[2]) { printf("Scalene\n"); }
}

int main(void) {
	while (scanf("%d %d %d", &a, &b, &c)) {
		if (a == 0 && b == 0 && c == 0) { break; }
		arr[0] = a; arr[1] = b; arr[2] = c;
		qsort(arr, 3, sizeof(int), compare);
		res();
	}
	return 0;
}