#include <iostream> #include <cstdio> using namespace std; int main(){ int n; int a[100005]; int c=0; for(int i =1;c<100000;++i){ if(i%3==0||i%5==0){ a[c++] = i; } } while(~scanf("%d",&n)){ printf("%d\n",a[n-1]); } }