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zoj 3228 - Searching the String

题目:给你一个长目标串str,和一些模式串,求每个串出现的次数。模式串有可覆盖和不可覆盖两种。

分析:字符串,多串匹配,AC自动机。由于数据有可能不允许相交,所以记录上一个的结束位置。

            题目的数据比较猥琐,可能相同,采用一个 Fath域记录第一次出现的 id,计算一次就可以了。

说明:注意数据有相同的串;该题可以使用 RK算法+二分。

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

char Word[10];
char Line[100005];
int  Walk[100005];
int  Fath[100005];

/* AC_DFA define */
#define nodesize 300005
#define dictsize 26

typedef struct node
{
    int   flag[2];
    int   last;
    int   deep;
    node* fail;
    node* next[dictsize];
}tnode;
tnode  dict[nodesize];
tnode* Q[nodesize];
int    ID[256];

class AC_DFA
{
    private:
        int    size;
        tnode* root;
    public:
        AC_DFA() {makeID();init();}
        void makeID() {
            for (int i = 0 ; i < dictsize ; ++ i)
                ID[i+'a'] = i;
        }
        void init() {
            memset(dict, 0, sizeof(dict));
            root=NULL;size=0;root=newnode();
        }
        tnode* newnode() {
            dict[size].fail = root;
            dict[size].last = -1; 
            return &dict[size ++];
        }
        void insert(char* word, int id, int s) {
            tnode* now = root;
            for (int i = 0 ; word[i] ; ++ i) {
                if (!now->next[ID[word[i]]])
                    now->next[ID[word[i]]] = newnode();
                now = now->next[ID[word[i]]];
            }
            /* 记录数据,相同的计入父节点 */
			if (!now->flag[s]) {
				now->deep = strlen(word);
				now->flag[s] = id;
			}else Fath[id] = now->flag[s];
        }
        void setfail() {
            Q[0] = root; root->fail = NULL;
            for (int move = 0,save = 1 ; move < save ; ++ move) {
                tnode* now = Q[move];
                for (int i = 0 ; i < dictsize ; ++ i)
                    if (now->next[i]) {
                        tnode* p = now->fail;
                        while (p && !p->next[i]) p = p->fail;
                        now->next[i]->fail = p?p->next[i]:root;
                        Q[save ++] = now->next[i];
                    }else now->next[i] = now==root?root:now->fail->next[i];//构建 Trie图 
            }
        }
        int query(char* line, int N) {
        	memset(Walk, 0, sizeof(Walk));
            tnode* now = root;
            for (int i = 0 ; line[i] ; ++ i) {
                now = now->next[ID[line[i]]];
                for (tnode* p = now ; p ; p = p->fail) {
                	if (p->flag[0]) ++ Walk[p->flag[0]];
                    if (p->flag[1] && p->last+p->deep <= i) {
                        p->last = i;
                        ++ Walk[p->flag[1]];
                    }
				}
            }
            for (int i = 1 ; i <= N ; ++ i)
                printf("%d\n",Walk[Fath[i]]);
            return 0;
        }
};
/* AC_DFA  end */
int main()
{
    int N,S,T = 1;
    AC_DFA ac;
    while (scanf("%s",Line) != EOF) {
        ac.init();
        scanf("%d",&N);
        for (int i = 1 ; i <= N ; ++ i) {
            scanf("%d %s",&S,Word);
            Fath[i] = i;
            ac.insert(Word, i, S);
        }
        ac.setfail();
        printf("Case %d\n",T ++);
        ac.query(Line, N);
        printf("\n");
    }
    return 0;
}


zoj 3228 - Searching the String