String Matching

题目1094：String Matching

时间限制：1 秒

内存限制：32 兆

特殊判题：否

提交：865

解决：446

题目描述：

    Finding all occurrences of a pattern in a text is a problem that arises frequently in text-editing programs. 
    Typically,the text is a document being edited,and the pattern searched for is a particular word supplied by the user.  
    We assume that the text is an array T[1..n] of length n and that the pattern is an array P[1..m] of length m<=n.We further assume that the elements of P and  T are all alphabets(∑={a,b...,z}).The character arrays P and T are often called strings of characters.  
    We say that pattern P occurs with shift s in the text T if 0<=s<=n and T[s+1..s+m] = P[1..m](that is if T[s+j]=P[j],for 1<=j<=m).  
    If P occurs with shift s in T,then we call s a valid shift;otherwise,we calls a invalid shift. 
    Your task is to calculate the number of vald shifts for the given text T and p attern P.

输入：

   For each case, there are two strings T and P on a line,separated by a single space.You may assume both the length of T and P will not exceed 10^6. 

输出：

    You should output a number on a separate line,which indicates the number of valid shifts for the given text T and pattern P.

样例输入：

abababab abab

样例输出：

3

#include<iostream>#include<string>using namespace std; int main(){    int i,j,t;    string s,ss;    while(cin>>s>>ss)    {         j=s.size();         for(i=t=0;i<j;++t)         {             if(s.find(ss,i)!=string::npos) i=s.find(ss,i)+1;             else break;         }         cout<<t<<endl;    }    return 0;}/**************************************************************    Problem: 1094    User: 3011216016    Language: C++    Result: Accepted    Time:170 ms    Memory:3052 kb****************************************************************/