Educational Codeforces Round 19 E. Array Queries 暴力

连接：

http://codeforces.com/contest/797/problem/E

题意：

给你一个a数组，q次询问，每次给你个p，k   每次操作使p=p+a[p]+k，直到p大于n为止

问一共操作了多少次

题解：

先预处理k不超过325时候的答案，当k大于325的时候就暴力算

代码：

#include <map>
#include <set>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <cstdlib>
#include <cstring>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define all(x) (x).begin(),(x).end()
#define pb push_back
#define mp make_pair
#define lson l,m,rt<<1  
#define rson m+1,r,rt<<1|1 
typedef long long ll;
typedef vector<int> VI;
typedef pair<int, int> PII;
const ll MOD = 1e9 + 7;
const int INF = 0x3f3f3f3f;
const int MAXN = 1e5 + 7;
// head

const int BLK = 325;
int a[MAXN], dp[BLK][MAXN];

int main() {
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    rep(i, 1, n + 1) cin >> a[i];
    rep(k, 1, BLK) per(p, 1, n + 1) {
        int q = p + a[p] + k;
        if (q > n) dp[k][p] = 1;
        else dp[k][p] = dp[k][q] + 1;
    }
    int q;
    cin >> q;
    while (q--) {
        int p, k;
        cin >> p >> k;
        if (k < BLK) cout << dp[k][p] << endl;
        else {
            int sum = 0;
            while (p <= n) p = p + a[p] + k, sum++;
            cout << sum << endl;
        }
    }
    return 0;
}