//lab6_2.c
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
void main() {
char a[100];
int i=0,j;
char c;
int flag=0;
while(scanf("%c",&c) != EOF ) {
    if(c=='\n') {a[i]=c; break;}
    else {a[i]=toupper(c); i++;}
    }
printf("Length is  %d\n",i);
if(i<3) exit(0);
for (j=2; j<i; j++) {
    if ( ( a[j] == a[j-1]+1) && (a[j-1] == a[j-2]+1) ) flag=1;
    }
if(flag == 1) printf("YES\n"); else printf("NO\n");
}