#include <stdio.h>
int main()
int a,b,c;{
scanf(" %d %d %d ",&a,&b,&c);
if(a<=0 || b<=0 || c<=0)
    printf("invalid input");
    else if (a==b && b==c){
    printf("equilateral");} 
    else if( a==b || b==c || a==c);
    printf("isoceles");
    else if{
    printf("scalene");
    }
    return 0;
}