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# include <bits/stdc++.h>
using namespace std ;
typedef long long LL ;
// 欧拉筛
const int N = 1e6 + 10 ;
int primes [ N ] , cnt ; // primes[]存储所有素数
bool st [ N ] ; // st[x]存储x是否被筛掉
void get_primes ( int n ) {
memset ( st , 0 , sizeof st ) ;
cnt = 0 ;
for ( int i = 2 ; i < = n ; i + + ) {
if ( ! st [ i ] ) primes [ cnt + + ] = i ;
for ( int j = 0 ; primes [ j ] * i < = n ; j + + ) {
st [ primes [ j ] * i ] = true ;
if ( i % primes [ j ] = = 0 ) break ;
}
}
}
int main ( ) {
int n ;
cin > > n ;
get_primes ( n ) ;
for ( int i = 0 ; i < cnt ; i + + ) {
int p = primes [ i ] ;
int s = 0 ;
// 思路：由大到小+除法降维
// 优点：
for ( int j = n ; j ; j / = p ) s + = j / p ;
printf ( " %d %d \n " , p , s ) ;
}
return 0 ;
}
