#import <stdio.h>
#import <stdbool.h>
int main() {
	char S[102];
	char *s = S;
	scanf("%s",s);
	bool c = false;
	while(*s!='\0'){
		if(*s=='C') c = true;
		if(c&&*s=='F'){
			puts("Yes");
			return 0;
		}
		s++;
	}
	puts("No");
}