#include <stdio.h>
int main() {
int a;
scanf("%d", &a);
int flag = 0;
while (a > 0) {
int last = a % 10;
a = a / 10;
if (n == 0) break;
int pre = n % 10;
if (last == pre) {
flag = 1;
break;
}
}
if (flag == 1)
printf("YES");
else
printf("NO");
return 0;
}