cf 12A

#include<bits\stdc++.h>

using namespace std;

int main()
{
   char x[3], y[3], z[3];
   scanf("%s %s %s", x, y, z);

   if(x[0] == z[2] && x[1] == z[1] && x[2] == z[0] && y[0] == y[2]) printf("YES\n");
   else printf("NO\n");
}