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UVALive-4670 AC自動機入門題 求出現次數最多的子串

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/**
鏈接:http://vjudge.net/problem/UVALive-4670
詳見lrj訓練指南P216
*/
#include<bits/stdc++.h>
using namespace std;
#define P pair<int,int>
#define ms(x,y) memset(x,y,sizeof x)
#define LL long long
const int maxn = 22;
const int mod = 1e9+7;
const int maxnode = 71*150;
const int sigma_size = 26;
map<string
,int> mp; int cnt[155]; struct AhoCorasickAutomata { int ch[maxnode][sigma_size]; int val[maxnode]; int sz; int f[maxnode]; int last[maxnode]; void clear(){sz = 1; memset(ch[0],0,sizeof ch[0]); } int idx(char c){return c-a; } void insert(char *s,int v) {
int u = 0, n = strlen(s); for(int i = 0; i < n; i++){ int c = idx(s[i]); if(!ch[u][c]){ memset(ch[sz], 0, sizeof ch[sz]); val[sz] = 0; ch[u][c] = sz++; } u = ch[u][c]; } val[u] = v; }
void find(char *T){ int n = strlen(T); int j = 0; for(int i = 0; i < n; i++){ int c = idx(T[i]); //while(j&&!ch[j][c]) j = f[j]; j = ch[j][c]; if(val[j]) print(j); else if(last[j]) print(last[j]); } } void print(int j) { if(j){ cnt[val[j]]++; print(last[j]); } } void getFail(){ queue<int> q; f[0] = 0; for(int c = 0; c < sigma_size; c++){ int u = ch[0][c]; if(u){f[u] = 0; q.push(u); last[u] = 0;} } while(!q.empty()){ int r = q.front(); q.pop(); for(int c = 0; c < sigma_size; c++){ int u = ch[r][c]; if(!u){ ch[r][c] = ch[f[r]][c]; continue; }//if(!u) continue; q.push(u); int v = f[r]; while(v&&!ch[v][c]) v = f[v]; f[u] = ch[v][c]; last[u] = val[f[u]] ? f[u] : last[f[u]]; } } } } ac ; char a[155][77]; char s[1000006]; int main() { int n; while(scanf("%d",&n)==1&&n) { ac.clear(); mp.clear(); memset(cnt, 0, sizeof cnt); for(int i = 1; i <= n; i++){ scanf("%s",a[i]); ac.insert(a[i],i); mp[string(a[i])] = i; } scanf("%s",s); ac.getFail(); ac.find(s); int mas = 0; for(int i = 1; i <= n; i++){ if(cnt[i]>mas){mas = cnt[i];} } printf("%d\n",mas); for(int i = 1; i <= n; i++){ if(cnt[mp[string(a[i])]]==mas){ printf("%s\n",a[i]); } } } return 0; }

UVALive-4670 AC自動機入門題 求出現次數最多的子串