全文检索

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)

Total Submission(s): 1048    Accepted Submission(s): 324

Problem Description

我们大家经常用google检索信息，但是检索信息的程序是很困难编写的；现在请你编写一个简单的全文检索程序。

问题的描述是这样的：给定一个信息流文件，信息完全有数字组成，数字个数不超过60000个，但也不少于60个；再给定一个关键字集合，其中关键字个数不超过10000个，每个关键字的信息数字不超过60个，但也不少于5个；两个不同的关键字的前4个数字是不相同的；由于流文件太长，已经把它分成多行；请你编写一个程序检索出有那些关键字在文件中出现过。

 

 

Input

第一行是两个整数M，N；M表示数字信息的行数，N表示关键字的个数；接着是M行信息数字，然后是一个空行；再接着是N行关键字；每个关键字的形式是：[Key No. 1] 84336606737854833158。

 

 

Output

输出只有一行，如果检索到有关键字出现，则依次输出，但不能重复，中间有空格，形式如：Found key: [Key No. 9] [Key No. 5]；如果没找到，则输出形如：No key can be found !。

 

 

Sample Input

20 10

646371829920732613433350295911348731863560763634906583816269

637943246892596447991938395877747771811648872332524287543417

420073458038799863383943942530626367011418831418830378814827

679789991249141417051280978492595526784382732523080941390128

848936060512743730770176538411912533308591624872304820548423

057714962038959390276719431970894771269272915078424294911604

285668850536322870175463184619212279227080486085232196545993

274120348544992476883699966392847818898765000210113407285843

826588950728649155284642040381621412034311030525211673826615

398392584951483398200573382259746978916038978673319211750951

759887080899375947416778162964542298155439321112519055818097

642777682095251801728347934613082147096788006630252328830397

651057159088107635467760822355648170303701893489665828841446

069075452303785944262412169703756833446978261465128188378490

310770144518810438159567647733036073099159346768788307780542

503526691711872185060586699672220882332373316019934540754940

773329948050821544112511169610221737386427076709247489217919

035158663949436676762790541915664544880091332011868983231199

331629190771638894322709719381139120258155869538381417179544

000361739177065479939154438487026200359760114591903421347697

[Key No. 1] 934134543994403697353070375063

[Key No. 2] 261985859328131064098820791211

[Key No. 3] 306654944587896551585198958148

[Key No. 4]338705582224622197932744664740

[Key No. 5] 619212279227080486085232196545

[Key No. 6]

333721611669515948347341113196

[Key No. 7] 558413268297940936497001402385

[Key No. 8] 212078302886403292548019629313

[Key No. 9] 877747771811648872332524287543

[Key No. 10] 488616113330539801137218227609

 

 

Sample Output

Found key: [Key No. 9] [Key No. 5]

题目大意：给定一段长数字串和一组短的数字串，问哪些短串在长串中出现过。

解题方法：AC自动机。

#include 
       
        #include 
        
         #include 
         
          #include 
          
           #include 
           
            #include 
            
             using namespace std;typedef struct node{ int id; node *fail; node *next[10]; node() { id = 0; fail = NULL; memset(next, 0, sizeof(next)); }}TreeNode;int res[10005];int nCount = 0;bool flag = false;void Insert(TreeNode *pRoot, char Substr[], int id){ int nLen = strlen(Substr); TreeNode *p = pRoot; for (int i = 0; i < nLen; i++) { int index = Substr[i] - '0'; if (p->next[index] == NULL) { p->next[index] = new TreeNode; } p = p->next[index]; } p->id = id;}void BuildAC(TreeNode *pRoot){ queue
             
               Queue; Queue.push(pRoot); while(!Queue.empty()) { TreeNode *p = Queue.front(); Queue.pop(); for (int i = 0; i < 10; i++) { if (p->next[i] != NULL) { if (p == pRoot) { p->next[i]->fail = pRoot; } else { TreeNode *temp = p->fail; while(temp != NULL) { if (temp->next[i] != NULL) { p->next[i]->fail = temp->next[i]; break; } temp = temp->fail; } if (temp == NULL) { p->next[i]->fail = pRoot; } } Queue.push(p->next[i]); } } }}void Query(TreeNode *pRoot, char str[]){ TreeNode *p = pRoot; int nLen = strlen(str); for (int i = 0; i < nLen; i++) { int index = str[i] - '0'; while(p != pRoot && p->next[index] == NULL) { p = p->fail; } p = p->next[index]; if (p == NULL) { p = pRoot; } TreeNode *temp = p; while(temp != pRoot && temp->id != -1) { if (temp->id > 0) { res[nCount++] = temp->id; temp->id = -1; flag = true; } temp = temp->fail; } }}void DeleteNode(TreeNode *pRoot){ for (int i = 0; i < 10; i++) { if (pRoot != NULL) { DeleteNode(pRoot->next[i]); } } delete pRoot;}int main(){ int m, n; scanf("%d%d", &m, &n); char temp[105]; char str[60001]; memset(str, 0, sizeof(str)); TreeNode *pRoot = new TreeNode; for (int i = 0; i < m; i++) { scanf("%s", temp); strcat(str, temp); } int num; for (int i = 0; i < n; i++) { while(1) { char ch = getchar(); if (ch == ']') { getchar(); break; } } scanf("%s", temp); Insert(pRoot, temp, i + 1); } BuildAC(pRoot); Query(pRoot, str); if (flag) { printf("Found key: "); for (int i = 0; i < nCount; i++) { printf(i == nCount - 1 ? "[Key No. %d]\n" : "[Key No. %d] ", res[i]); } } else { printf( "No key can be found !\n" ); } DeleteNode(pRoot); return 0;}