task2.c

include <stdio.h>

int main()
{
double a, b, c;

scanf_s("%lf%lf%lf" , &a, &b, &c);
if (a + b > c and a + c > b and b + c > a)
    printf("能构成三角形\n");
else
	printf("不能构成三角形\n");

	return 0;

}