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：
1 #include <map> 2 #include <set> 3 #include <cmath> 4 #include <queue> 5 #include <stack> 6 #include <cstdio> 7 #include <string> 8 #include <vector> 9 #include <cstdlib> 10 #include <cstring> 11 #include <sstream> 12 #include <iostream> 13 #include <algorithm> 14 #include <functional> 15 using namespace std; 16 #define rep(i,a,n) for (int i=a;i<n;i++) 17 #define per(i,a,n) for (int i=n-1;i>=a;i--) 18 #define all(x) (x).begin(),(x).end() 19 #define pb push_back 20 #define mp make_pair 21 #define lson l,m,rt<<1 22 #define rson m+1,r,rt<<1|1 23 typedef long long ll; 24 typedef vector<int> VI; 25 typedef pair<int, int> PII; 26 const ll MOD = 1e9 + 7; 27 const int INF = 0x3f3f3f3f; 28 const int MAXN = 1e5 + 7; 29 // head 30 31 const int BLK = 325; 32 int a[MAXN], dp[BLK][MAXN]; 33 34 int main() { 35 ios::sync_with_stdio(false); 36 int n; 37 cin >> n; 38 rep(i, 1, n + 1) cin >> a[i]; 39 rep(k, 1, BLK) per(p, 1, n + 1) { 40 int q = p + a[p] + k; 41 if (q > n) dp[k][p] = 1; 42 else dp[k][p] = dp[k][q] + 1; 43 } 44 int q; 45 cin >> q; 46 while (q--) { 47 int p, k; 48 cin >> p >> k; 49 if (k < BLK) cout << dp[k][p] << endl; 50 else { 51 int sum = 0; 52 while (p <= n) p = p + a[p] + k, sum++; 53 cout << sum << endl; 54 } 55 } 56 return 0; 57 }
