#include<stdio.h>
int main()
{
    int a,b,c;
    scanf("%d %d %d",&a,&b,&c);
    if('all sides equal')
    {
        printf("equilateral");
    }
    if else('two sides equal')
    {
        printf("isosceles");
    }
    if else('all sides different')
    {
        printf("Scalene");
    }
    else
    {
        printf("invalid input");
    }
    return 0;
}