HDU 4787 GRE Words Revenge 在线AC自动机

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题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=4787

构造两个自动机当一个自动机大于节点上限，就将BUFF全部加入AC
有个问题就是TOP在1000的时候能AC 5000和500就会WA不是很懂为什么

代码：

#include <bits/stdc++.h>#define sf scanf#define pf printfusing namespace std;const int maxn = 100000 + 10;struct AcTrie{    int ch[maxn][2],tot,v[maxn],fail[maxn];    void Init(){        memset( ch[0] , 0 ,sizeof ch[0]);        v[0] = 0;        tot = 1;    }    int NewNode(){        memset( ch[tot] , 0, sizeof ch[0] );        v[tot] = 0;        return tot++;    }    void Insert(char * s){        int cur = 0;        while(*s){            int idx = *s - '0';            if(!ch[cur][idx]){                ch[cur][idx] = NewNode();            }            cur = ch[cur][idx];            s++;        }        v[cur] = 1;    }    void GetFail(){        queue<int> Q;Q.push(0);        fail[0] = -1;        while(!Q.empty()){            int cur = Q.front();Q.pop();            for(int idx = 0;idx < 2;++idx){                if(ch[cur][idx]){                    int f = fail[cur];                    while(~f && !ch[f][idx]) f = fail[f];                    fail[ch[cur][idx]] = (f == -1) ? 0 : ch[f][idx];                    Q.push(ch[cur][idx]);                }            }        }    }    int Search(char *s){        int cur = 0,ret = 0,f;        while(*s){            int idx = *s - '0';            if(!ch[cur][idx]){                f = fail[cur];                while(f != -1 && !ch[f][idx]) f = fail[f];                cur = (f == -1) ? 0 : ch[f][idx];            }else cur = ch[cur][idx];            f = cur;            while(f){                ret += v[f];                f = fail[f];            }            s++;        }        return ret;    }}ac,buff;const int maxnn = 5000000 + 50,TOP = 999;char str[maxnn],tmp[maxnn];void DFS(int rt1,int rt2){    ac.v[rt1] = ac.v[rt1] | buff.v[rt2];    for(int i = 0;i < 2;++i){        if(ac.ch[rt1][i] && buff.ch[rt2][i]) DFS(ac.ch[rt1][i],buff.ch[rt2][i]);        else if(!ac.ch[rt1][i] && buff.ch[rt2][i]) DFS(ac.ch[rt1][i] = ac.NewNode(),buff.ch[rt2][i]);    }}void getRev(int k){    int len = strlen(str + 1);    char* tmp_s = str + 1,*tmp_tmp = tmp + 1;    tmp_tmp[len] = 0;    for(int i = 0;i < len;++i) tmp_tmp[i] = tmp_s[ (i + k) % len ];}int main(){    int T,ca = 0;sf("%d",&T);    tmp[0] = '#';    while( T-- ){        int n,pre = 0;sf("%d",&n);        ac.Init();        buff.Init();        ac.GetFail();        buff.GetFail();        pf("Case #%d:\n",++ca);        for(int i = 0;i < n;++i){            sf("%s",str);            getRev(pre);            if(str[0] == '+') buff.Insert(tmp + 1);            else{                if(buff.tot > TOP){                    DFS(0,0);                    ac.GetFail();                    buff.Init();                    buff.GetFail();                }                else buff.GetFail();                pf("%d\n",pre = (buff.Search(tmp + 1) + ac.Search(tmp + 1)));            }        }    }}

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