online_judge_1048

#include<stdio.h>
int main()
{
	int a,b,c;
	while(scanf("%d%d%d",&a,&b,&c)!=EOF)
	{
		if(a>=b+c||b>=a+c||c>=a+b||a<=0||b<=0||c<=0)
			continue;
		else if(a*a==b*b+c*c||b*b==a*a+c*c||c*c==a*a+b*b)
			printf("直角三角形\n");
		else if(a*a>b*b+c*c||b*b>a*a+c*c||c*c>a*a+b*b)
			printf("钝角三角形\n");
		else
			printf("锐角三角形\n");
	}
	return 0;
}