798A.cpp

#include<bits/stdc++.h>


using namespace std;

int main(){

    int i,j,k;
    int n;
    string s;

    cin>>s;
    n=s.length();

    if(n%2==0){

        j=n-1;k=0;

        for(i=0;i<n/2;i++){

            if(s[i]!=s[j])

                k++;
            j--;
        }

        if(k==1)
            cout<<"YES";
        else
            cout<<"NO";
    }

    else{
        j=n-1;k=0;
        for(i=0;i<n/2;i++,j--){
            if(s[i]!=s[j])
                k++;
        }

        if(k<=1)
            cout<<"YES";
        else
            cout<<"NO";
    }

    return 0;
}