Turtles (非纯分块)

http://codeforces.com/contest/103/problem/D

 #include <bits/stdc++.h>
 using namespace std;
 typedef long long ll;
 #define faster ios::sync_with_stdio(0);cin.tie(0)

 inline ll read()
 {
     int x=,f=;char ch=getchar();
     while(ch<''||ch>''){if(ch=='-')f=-;ch=getchar();}
     while(ch>=''&&ch<=''){x=x*+ch-'';ch=getchar();}
     return x*f;
 }

 /********************************************************************/

 const int maxn = 3e5+;
 ll n, m;
 ll a[maxn];
 ll cx[maxn], cy[maxn];
 int kiss = ;
 vector<int> d[];
 ll dp[maxn];
 ll ans[maxn];

 int main(){
     n = read();
     for(int i = ;i <= n;i++)
         a[i] = read();
     m = read();
     for(int i = ;i <= m;i++){
         cx[i] = read(), cy[i] = read();
         if(cy[i] < kiss)
             d[cy[i]].push_back(i);
         else{
             ll ans1 = ;
             for(int j = cx[i];j <= n;j += cy[i]){
                 ans1 += a[j];
             }
             ans[i] = ans1;
         }
     }
     for(int i= ;i < kiss;i++){
         if(d[i].size()){
             for(int j = n;j;j--){       //From the back forward
                 if(j+i > n)
                     dp[j] = a[j];
                 else
                     dp[j] = dp[j+i] + a[j];
             }
             for(int j = ;j < d[i].size();j++)
                 ans[d[i][j]] = dp[cx[d[i][j]]];
         }
     }
     for(int i = ;i <= m;i++)
         cout << ans[i] << endl;
     return ;
 }