from math import *
def crible(n):
    L=[i for i in range(0,n+1)]
    for i in range(2,int(floor(sqrt(n)))+1):
        if L[i]>=1:
            for k in range(2,int(floor(n/i))+1):
                L[i*k]=0
    i=0
    while i<len(L):
        if L[i]==0 or L[i]==1:
            L.remove(L[i])
        else:
            i+=1
    return L, len(L))