URAL 1732. Ministry of Truth ( KMP 多模式串匹配 )

问在第一个串中删掉几个字符能否得到第二个串。注意在第二个串中不连续的单词在第一个串中也必须不连续。

一组数据：

Input:

abababbbbabab
bb aba ab

Output:

I HAVE FAILED!!!

#include <cstdio>

#include <cstring>

#include <cstdlib>



using namespace std;



const int MAXN = 100100;



char str[MAXN];

char tmp[MAXN];

int nextval[MAXN];

int flag[MAXN];

int strL, tmpL;



void getNextval( char* s, int* nextval, int length )

{

    int i=0,j=-1;

    nextval[0]=-1;

    while(i<length)

    {

        if(j==-1||s[i]==s[j])

        {

            ++i;

            ++j;

            //next[i]=j;

            if (s[i]!=s[j])

                nextval[i]=j;

            else

                nextval[i]=nextval[j];

        }

        else

            j=nextval[j];

    }

}



int KMP( char *t, char *s, int lenth, int len )   //s为主串，t为模式串

{

    getNextval( t, nextval, lenth );

    int i = 0, j = 0;

    while ( j < len )

    {

        if ( i == -1 || s[j] == t[i] )

        {

            ++i, ++j;

            if ( i == lenth ) return j;

        }

        else i = nextval[i];

    }

    return -1;

}



int main()

{

    while ( gets( str ) != NULL )

    {

        strL = strlen(str);

        memset( flag, -1, sizeof(flag) );

        bool ok = true;

        int i = 0;

        while ( 1 )

        {

            scanf( "%s", tmp );

            tmpL = strlen(tmp);



            int ans = KMP( tmp, &str[i], tmpL, strL - i );



            //puts(tmp);

            //puts(&str[i]);



            if ( ans == -1 ) ok = false;

            else flag[ i + ans - tmpL ] = tmpL;



            char ch = getchar();



            if ( ch == '\n' ) break;

            i += ans + 1;

        }

        if ( ok )

        {

            for ( int i = 0; i < strL; ++i )

            {

                if ( str[i] == ' ' ) putchar(' ');

                else if ( flag[i] == -1 ) putchar('_');

                else

                {

                    for ( int j = 0; j < flag[i]; ++j )

                        putchar( str[i+j] );

                    i += flag[i] - 1;

                }

            }

            puts("");

        }

        else puts("I HAVE FAILED!!!");

    }

    return 0;

}