#include<stdio.h>
int main()
{
    int a,b,c;
    scanf("%d",&a);
    scanf("%d",&b);
    scanf("%d",&c);
    if(a+b>c&&a+c>b&&b+c>a);
          {if(a==b||b==c||a==c)
             {if(a==b&&a==c&&b==c) printf("equilateral triangle.\n");
             else printf("isoceles triangle.\n");}
           else printf("triangle.\n");}
    else printf("non-triangle.\n");0
    return 0;
}