HDU 1686 Oulipo The maximum number of small strings (KMP) to be matched in a large string

http://acm.hdu.edu.cn/showproblem.php?pid=1686

Oulipo

Time limit:3000/1000 MS (java/others) Memory limit:32768/32768 K (java/others)
Total submission (s): 6098 Accepted Submission (s): 2448

Problem DescriptionThe French author Georges perec (1936–1982) once wrote a book, La disparition, without the letter ' E '. He was a member of the Oulipo group. A quote from the book:

Tout avait Pair normal, mais Tout s ' affirmait faux. Tout avait Fair normal, d ' Abord, puis surgissait l ' inhumain, l ' affolant. Il aurait voulu savoir oùs ' articulait l ' association qui l ' unissait au roman:stir son tapis, Assaillantàtout instant s On imagination, l ' intuition d ' un tabou, la vision d ' un mal obscur, d ' un quoi vacant, d ' UN non-dit:la vision, l ' avision D ' Un oubli commandant tout, oùs ' abolissait la raison:tout avait l ' air normal mais ...

Perec would probably has scored high (or rather, low) in the following contest. People is asked to write a perhaps even meaningful text on some subject with as few occurrences of a given "word" as poss Ible. Our tasks are to provide the jury with a program that counts these occurrences, in order to obtain a ranking of the Competit Ors. These competitors often write very long texts with nonsense meaning; A sequence of 500,000 consecutive ' T ' is not unusual. And they never use spaces.

So we want to quickly find out what often a word, i.e., a given string, occurs in a text. More Formally:given the alphabet {' A ', ' B ', ' C ', ..., ' Z '} and both finite strings over that alphabet, a word W and a text T , count the number of occurrences of W in T. All the consecutive characters of W must exactly match consecutive characters of T. occurrences may overlap.

Inputthe first line of the input file contains a single number:the number of test cases to follow. Each test case has the following format:

One line with the word W, a string over {' A ', ' B ', ' C ', ..., ' Z '}, with 1≤| w| ≤10,000 (Here | w| Denotes the length of the string W).
One line with the text T, a string over {' A ', ' B ', ' C ', ..., ' Z '}, with | w| ≤| T| ≤1,000,000.

Outputfor every test case in the input file, the output should contain a single number, on a single line:the number of OC Currences of the word W in the text T.

Sample Input3bapcbapcazaazazazaverdiaverdxivyerdian

1#include <iostream>2#include <stdlib.h>3#include <stdio.h>4#include <cstring>5 using namespacestd;6 intn,m,nxt[10005],kk,t;7 Charb[10005],a[1000005];8 ///This topic adds multiple matches on the base KMP. 9 ///It means that after we've matched the string, we're going to jump to the right place and continue looking forTen ///continue to use KMP's ideas. Some locations have already been matched, so don't match them.  One ///xxxxxxxabbaab*xxxxxx A ///Abbaaba - //our position after jumping Abbaaba and jumping position is related to next array - voidbuildnxt () the { -    intj,k; -m=strlen (b); -nxt[0]=-1; +j=0; k=-1; -      while(j<m) +     { A         if((k==-1)|| b[j]==B[k]) at         { -J + +; -k++; -nxt[j]=K; -         } -         Elsek=Nxt[k]; in     } - } to intKMP () + { -     intk=0, l=0, cou=0; then=strlen (a); *     intANS=M,KK=NXT[M];///ans in string subscript, and starting distance ans+1 $      while(1)Panax Notoginseng     { -         if(kk!=0&&kk!=-1) {ans=kk;kk=Nxt[ans];} the         Else  Break; +}///to find the smallest jumping point, return from the next end to find the first non-negative value.  A      while(k<N) the     { +         if((l==-1)|| a[k]==B[l]) -         { $k++; $l++; -         } -         ElseL=Nxt[l]; the         if(l==m) -         {Wuyicou++; the             if(kk==0)Continue;///If the end of the next array is 0, there is no repetition in the matching substring in the main string.  -             ///In other words, there is no point in the matching main string that can jump.  Wu             if(k==n-1) Break;///if K is already at the end of the main string, you cannot have a string that continues to match.  -K=k-l+ans;///K-L (starting point) +ans AboutL=0; $         } -     } -     returncou; - } A intMain () + { thescanf"%d",&t); - GetChar (); $      while(t--) the     { the gets (b); the gets (a); thememset (NXT,0,sizeof(NXT)); - buildnxt (); inprintf"%d\n", KMP ()); the     } the     return 0; About}

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HDU 1686 Oulipo The maximum number of small strings (KMP) to be matched in a large string