？？？？

#include<iostream>
using namespace std;
char a[108];
int main(){
	char ch;
	int i=0;
	while(scanf("%c",&ch)&&ch!='\n'){
		a[i++]=ch;
	}
	bool x=1;
	for(int j=0;j<i;j++){
		if(a[j]!=a[i-j-1]){
			x=0;
			break;
		}
	}
	if(x){
		cout<<"yes";
	}else{
		cout<<"no";
	}
	return 0;
}