#include <stdio.h>
int main(void) {
    unsigned long     a,b,c;
    int rb,rc,rr;
    scanf( "%ld", &a );
    scanf( "%ld", &b );
    scanf( "%ld", &c );
    rb = (a+b-1) / b;
    rr = (rb + rb) / 3;
    if( rr == 0 ) rr = 1;
    rc = rr * c;
//printf("%d(%d)=>%d\n",rb,rr,rc);
    if ( a <= rc ) {
        printf("YES\n");
    } else {
        printf("NO\n");
    }
	return 0;
}