#include<iostream>
#include<algorithm>
using namespace std;
int main(){
	int a[3],iamwater,iamgood,aaa,bbb;
	a[0]=0;
	a[1]=0;
	a[2]=0;
	bool b;
	cin>>a[0]>>a[1]>>a[2];
	if(a[0]+a[1]>a[2]&&a[0]+a[2]>a[1]&&a[2]+a[1]>a[0])
	iamwater++;
	else
	{
	cout<<"Not triangle";
	return 0;
	}
	
	if(a[0]==a[1]==a[2]){
		cout<<"Acute triangle"<<endl;
		cout<<"Isosceles triangle"<<endl;
		cout<<"Equilateral triangle"<<endl;
		return 0;
	}
	sort(a,a+3);
	if((a[0]==a[1])||(a[1]==a[2])||(a[0]==a[3]))
	b=1;
	else
	b=0;
	aaa=a[0]*a[0]+a[1]*a[1];
	bbb=a[2]*a[2];
	if(aaa>bbb)
	cout<<"Acute triangle"<<endl;
	else if(aaa==bbb)
	cout<<"Right triangle"<<endl;
	else if(aaa<bbb)
	cout<<"Obtuse triangle"<<endl;
	if(b==1)
	cout<<"Isosceles triangle";
	return 0;
}

一直判断不出等边。