#include<stdio.h>
int main()
{
    int a,b,c;
    scanf("%d %d %d",&a,&b,&c);
    if(a<=0||b<=0||c<=0||a>=100||b>=100||c>=100){
        printf("invalid input");
    } 
    else if(a==b && b==c){
        printf("E")
    }
}