n=int(input())
x=[0]*1000
i=1
for a in range(1,10):
    j=i+i+1

    for k in range(i,j):
        if k<1000:x[k]=a
    i=j
ans=0
for i in range(1,n+1):
    ans*=10
    ans+=x[i]
print(ans)