#include<stdio.h>

int main(){
    int a,b,c;
    scanf("%d,%d,%d",&a &b &c);
    
    if(a<0 && b<0){
       printf("invalid input");
       return 0;    
    }
    
    if (a == b && b == c)
    printf("equilateral");
    else if (a == || b == c || a == c)
    printf("isosceles");
    else
    printf("scalene");
    
    return 0;
}