#include<stdio.h>

const char s[]="1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545";

void run(void){
  int d;
  scanf("%d",&d);
  printf("%c\n",s[d-1]);
}

int main(void){
  run();
  return 0;
}