m = int(input())

if m == 0:
  print("a")
  exit()
dp = [1,1,1]
now = 1
last = [1]
while True:
  a = dp[0] + 1
  b = dp[1] + a
  c = dp[2] + b
  if c <= m:
    dp = [a,b,c]
    now += 1
    last.append(c)
  else:break

difs = [1]
for i in range(1, len(last)):
  difs.append(last[i] - last[i-1])

left = m - last[-1]

pos = []
for i in range(len(difs))[::-1]:
  if left >= difs[i] :
    cnt = left//difs[i]
    left %= difs[i]
    pos.append([now - i - 1, cnt])

for i in range(now):
  pos.append([i, 10**18])

pos.sort()
ans = []
for _, (i,num) in enumerate(pos):
  if num == 10**18:
    ans.append("con")
  else:
    ans.append("c"*num)
  

print("".join(ans))