bzoj2002: [Hnoi2010]Bounce 弹飞绵羊 (分块)

 1#include <cstdio>
 2#include <cstring>
 3#include <iostream>
 4#include <algorithm>
 5#include <vector>
 6#include <queue>
 7#include <set>
 8#include <map>
 9#include <string>
10#include <cmath>
11#include <cstdlib>
12#include <ctime>
13#define fst first
14#define sec second
15#define lson l,m,rt<<1
16#define rson m+1,r,rt<<1|1
17#define ms(a,x) memset(a,x,sizeof(a))
18typedef long long LL;
19#define pi pair < int ,int >
20#define MP make_pair

 1using namespace std;
 2const double eps = 1E-8;
 3const int dx4[4]={1,0,0,-1};
 4const int dy4[4]={0,-1,1,0};
 5const int inf = 0x3f3f3f3f;
 6const int N=2E5+7;
 7int n,m;
 8int siz = 450; //sqrt(2E5)
 9int a[N];
10int pos[N];
11int cnt[N];
12int nxt[N];
13int end[N];

 1void go( int x)
 2{
 3    int ans = 0  ;
 4    while (1)
 5    {
 6	if (x>=n)
 7	{
 8	    printf("%d\n",ans);
 9	    break;
10	}
11	ans +=cnt[x];
12	x = nxt[x];
13//	cout<<"nxt[x]:"<<nxt[x]<<endl;
14    }
15}
16void update ( int i,int j)
17{
18    if (j>=n)
19    {
20	cnt[i]=1;
21	nxt[i]=n;
22	end[i]=i;
23    }
24    else
25    {
26	if (pos[i]==pos[j])
27	{
28	    cnt[i] = cnt[j] + 1;
29	    nxt[i] = nxt[j];
30	    end[i]=end[j];
31	}
32	else
33	{
34	    cnt[i] = 1;
35	    nxt[i] = j;
36	    end[i] = end[j];
37	}
38    }
39}
40int main()
41{
42	#ifndef  ONLINE_JUDGE 
43	freopen("code/in.txt","r",stdin);
44  #endif

1	scanf("%d",&n);
2	for ( int i = 0 ; i < n ;i++)
3	{
4	    scanf("%d",&a[i]);
5	    pos[i] = i/siz;
6	}

 1	scanf("%d",&m);
 2	while (m--)
 3	{
 4	    int opt;
 5	    scanf("%d",&opt);
 6	    if (opt==1)
 7	    {
 8		int x;
 9		scanf("%d",&x);
10		go(x);
11	    }
12	    else
13	    {
14		int x,y;
15		scanf("%d %d",&x,&y);
16		a[x]=y;
17		update(x,x+a[x]);
18		int p = pos[x]*siz;
19		for ( int i = x-1  ; i >= p ; i--) update(i,i+a[i]);
20	    }
21	}

1  #ifndef ONLINE_JUDGE  
2  fclose(stdin);
3  #endif
4    return 0;
5}