Cod sursa(job #2421272)

Utilizator BlaugranasEnal Gemaledin Blaugranas Data 14 mai 2019 17:13:55
Problema Aho-Corasick Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.84 kb
#include <fstream>
#include <vector>
#include <cstring>
#define ch(c) (c - 'a')

using namespace std;

ifstream cin("ahocorasick.in");
ofstream cout("ahocorasick.out");

struct trie {
    trie *son[26], *Next;
    int val;
    trie() {
        Next = 0;
        memset(son,0,sizeof(son));
        val = 0;
    }
};

const int SMAX = 1000002, LMAX = 10002, NMAX = 102;
char A[SMAX], S[NMAX][LMAX];
int N;
trie *T, *leaf[NMAX];

trie *insert(trie *t,char *str) {
    if(*str == 0) return t;
    if(t->son[ch(*str)] == 0) t->son[ch(*str)] = new trie;
    t = t->son[ch(*(str++))];
    return insert(t,str);
}

void readData() {
    cin.getline(A,SMAX);
    cin>>N;
    cin.get();
    for(int i = 0;i < N;i++) {
        cin.getline(S[i],LMAX);
    }
}

void buildTrie() {
    T = new trie;
    for(int i = 0;i < N;i++) {
        leaf[i] = insert(T,S[i]);
    }
}

void ahoCorasick() {
    buildTrie();
    vector<trie*> Q;
    Q.push_back(T);
    trie *v, *w;
    for (int left = 0; left < (int)Q.size();) {
        v = Q[left++];
        for(int i = 0;i < 26;i++) {
            if(v->son[i] != 0) {
                for(w = v->Next;w && w->son[i] == 0;) w = w->Next;
                v->son[i]->Next = w ? w->son[i] : T;
                Q.push_back(v->son[i]);
            }
        }
    }
    v = T;
    for(int i = 0;A[i] != 0;i++) {
        while(v && v->son[ch(A[i])] == 0) v = v->Next;
        if(!v) {
            v = T;
        } else {
            v = v->son[ch(A[i])];
            v->val++;
        }
    }

    for(int i = (int)Q.size() - 1;i >= 0;i--) {
        if(Q[i]->Next != 0)   {
            Q[i]->Next->val += Q[i]->val;
        }
    }

    for(int i = 0;i < N;i++) {
        cout << leaf[i]->val <<"\n";
    }
}

int main()
{
    readData();
    ahoCorasick();
    return 0;
}