洛谷 P1445 [Violet]樱花

 1 #include<cstdio>
 2 #include<algorithm>
 3 #include<cstring>
 4 #include<vector>
 5 using namespace std;
 6 #define fi first
 7 #define se second
 8 #define mp make_pair
 9 #define pb push_back
10 typedef long long ll;
11 typedef unsigned long long ull;
12 typedef pair<int,int> pii;
13 #define md 1000000007
14 int num[1001000];
15 bool vis[1001000];
16 int d[1001000];
17 int n;
18 ll ans=1;
19 int main()
20 {
21     ll i,j;
22     scanf("%d",&n);
23     //n=1000000;
24     for(i=2;i<=n;i++)    d[i]=i;
25     for(i=2;i<=n;i++)
26         if(!vis[i])
27             for(j=i;j<=n;j+=i)
28             {
29                 vis[j]=1;
30                 while(d[j]%i==0)    d[j]/=i,num[i]++;
31             }
32     for(i=1;i<=n;i++)    num[i]*=2,ans=ans*(num[i]+1)%md;
33     printf("%lld",ans);
34     return 0;
35 }