#include
using namespace std;
int main()
{
int a, b, c;
cin >> a >> b >> c;
if ((a + b > c) && (a + c > b) && (b + c > a))
{
if ((a == b) && (b == c) && (a == c))
{
cout << "等边三角形";
}
else if ((a == b) || (a == c) || (b == c))
{
cout << "等腰三角形";
}
else
{
cout << "三角形";
}
}
return 0;
}