#include <math.h>
#include <stack>
#include <stdio.h>
#include <iostream>
#include <vector>
#include <iomanip>
#include <string.h>
#include <algorithm>
using namespace std;
#define LL long long
const int N = 1e5 + 10;
const int INF = 0x3f3f3f3f;
int main()
{
    char a[1000];
    cin >> a;
    int len = strlen(a);
    bool flag = true;
    for(int i = 0; flag && i < len; i++)
    {
        if(a[i] != a[len - 1 - i])
            flag = false;
    }
    if(flag)
        cout << "yes";
    else
        cout <<"no";
    return 0;
}```