POJ 1226 Substrings KMP

KMP.

暴力strstr也轻松过.

//#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<iostream>
#include<sstream>
#include<cmath>
#include<climits>
#include<string>
#include<map>
#include<queue>
#include<vector>
#include<stack>
#include<set>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define pb(a) push_back(a)
#define INF 0x1f1f1f1f
#define lson idx<<1,l,mid
#define rson idx<<1|1,mid+1,r
#define PI  3.1415926535898
template<class T> T min(const T& a,const T& b,const T& c) {
    return min(min(a,b),min(a,c));
}
template<class T> T max(const T& a,const T& b,const T& c) {
    return max(max(a,b),max(a,c));
}
void debug() {
#ifdef ONLINE_JUDGE
#else

    freopen("d:\\in.txt","r",stdin);
   // freopen("d:\\out1.txt","w",stdout);
#endif
}
int getch() {
    int ch;
    while((ch=getchar())!=EOF) {
        if(ch!=' '&&ch!='\n')return ch;
    }
    return EOF;
}

void GetNext(const char *s ,int *next)
{
    int len=strlen(s);
    next[0]=next[1]=0;
    for(int i=2;i<=len;i++)
    {
        int j=next[i-1];
        if(j&&s[j]!=s[i-1])j=next[j];
        if(s[j]==s[i-1])next[i]=j+1;
        else next[i]=0;
    }
}
void reversal( char *s)
{
    int len=strlen(s);
    for(int i=0,j=len-1;i<j;i++,j--)
        swap(s[i],s[j]);
}
void strcut(char *sub,char *p,char *ed)
{
    int k=0;
    for(;p!=ed;p++,k++)
    {
        sub[k]=*p;
    }
    sub[k]='\0';
}
char dic[110][110];
int n;
int judge(char *sub1)
{
    int next1[110],next2[110];
    char sub2[110];
    int len=strlen(sub1);
    for(int i=0;i<len;i++)
        sub2[i]=sub1[len-i-1];
    GetNext(sub1,next1);
    GetNext(sub2,next2);
    for(int k=1;k<n;k++)
    {
        int f1=0,f2=0;
        int j;
        j=0;
        for(int i=0;dic[k][i]!='\0';)
        {
            if(sub1[j]==dic[k][i])
            {
                j++;i++;
                if(j==len)
                {
                    f1=1;break;
                }
            }else
            {
                if(j==0)i++;
                else j=next1[j];
            }
        }

        j=0;
        for(int i=0;dic[k][i]!='\0';)
        {
            if(sub2[j]==dic[k][i])
            {
                j++;i++;
                if(j==len)
                {
                    f2=1;break;
                }
            }else
            {
                if(j==0)i++;
                else j=next2[j];
            }
        }
        if((!f1)&&(!f2))return 0;
    }
    return 1;
}
int main()
{
    int t;
    scanf("%d",&t);
    for(int ca=1;ca<=t;ca++)
    {
        scanf("%d",&n);
        for(int i=0;i<n;i++)
            scanf("%s",dic[i]);
        int maxx=0;
        char sub[110];
        int len=strlen(dic[0]);
        for(int i=0;i<len;i++)
        {
            for(int j=i+maxx+1;j<=len;j++)
            {
                strcut(sub,dic[0]+i,dic[0]+j);
                if(judge(sub))
                {
                    maxx=j-i;
                }
            }
        }
        printf("%d\n",maxx);
    }
    return 0;
}