#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX 12
char *hoge(char* read);
int main()
{
char read[MAX] = {'\0'};
char *result;
fgets(read,MAX,stdin);
result = hoge(read);
printf("%s \n",result);
free(result);
return 0;
}
char *hoge(char* read)
{
int point = atoi(read);
char *rc = malloc(MAX);
int x ,k,j;
unsigned prime[MAX];
prime[0] = 2; x = 1; k = 1;
while (k < MAX) {
x += 2; j = 0;
while (j < k && x % prime[j] != 0) j++;
if (j == k) prime[k++] = x;
}
sprintf(rc,"%u",prime[--point]);
return rc;

}