#include<stdio.h>
int main()
{
    int n1,n2,n3;
    scanf("%d %d %d",&n1,&n2,&n3);
    if(n1<=0||n2<=0||n3<=0)
    {
        printf("Invalid input");
    }
    else if(n1==n2&&n2==n3)
    {
        printf("equilateral")
    }
    else if(n1==n2||n2==n3||n1==n3)
    {
        printf("isosceles")
    }
    else
    {
        printf("scalence")
    }
    return 0;
}