#include <stdio.h>            /* The C input/output library */

int main() {                  /* C programs always start with this header */

    int x;                    /* Declare a variable to hold the input number */

    scanf("%d", &x);          /* Input the number typed on the screen */

    if (x > 0)                /* Check if the number is > 0 (i.e., positive) */
        printf("yes");        /*   If so, output "yes" to the screen */
    else                      /*   If not, */
        printf("no");         /*      output "no" to the screen */

}                             /* End of main program (matches the "{") */