#include<stdio.h>
#include<stdlib.h>

void calc(int n,char s){
  if(n==0){
    putchar('\n');
    return;
  }

  int k=1;
  int t=1;
  while(t+k/2+1<=n){
    t+=k/2+1;
    k++;
  }
  int i;
  for(i=0;i<k;i++){
    putchar((char)(s+i%2));
  }
  calc(n-t,s+2);
  return;
}

void run(void){
  int n;
  scanf("%d",&n);
  calc(n,'a');
  return;
}

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