作者：李卓航         更新时间：2025-01-17 10:04          浏览：169次         点赞：0次          热度：28

''' m=int(input()) n=int(input()) L=[] if m>n: m,n=n,m for i in range(m,n+1): if i%7==0 and i%5 != 0: L.append(str(i)) print(",".join(L)) n=int(input()) L=[] for i in range(1,n+1): L.append(i) j=0 while True: a=L.pop(0) if (j+1)%3==0: pass else: L.append(a) if len(L)==1: break j+=1 print(L[0]) n=list(eval(input())) L=[] for i in n: if i<0: L.append(i+1) else: L.append(i) s=0 x=0 for i in range(len(L)-1): if L[i]<L[i+1]: s+=(L[i+1]-L[i])*1 else: x+=(L[i]-L[i+1])*0.3 print(s+x) ''' n=int(input()) d=0 for i in range(10,n+1): f=1 for j in range(2,i): if i%j==0: f=0 break if f==1: i=i//10 f=1 for j in range(2,i): if i%j==0: f=0 break d+=1 print(d)