# kmp+ Differential Article filter (filter)

Source: Internet
Author: User

Description

Given some short strings, you are asked to change these short strings into \ (*\) in a long string.

Input

The first line includes an integer \ (n\)that represents the number of short strings.

The next \ (n\) line is a short string of \ (n\) .

The last line, for the long string you need to change.

Output

A row that represents the long string after the change.

PS: Long string will have a variety of characters, short string contains only English characters

Sample input

3

Int

Ing

Kitty

Int is interesting! ~owo~

Sample output

\ (***\) is \ (***\)erest\ (***\)ing! ~owo~

Some of the inputs and outputs above are full-width, which is actually half-width.

This problem has a lot of ah, can be hashed, can be AC automata, can be KMP.

Let's talk about the KMP algorithm here.

The procedure is \ (kmp+\) differential.

You first need to convert all the letters in the long string to lowercase (uppercase).

\ (isalpha\) roar.

We find its \ (next\) array for each short string. Enumerate these strings and long string matches again.

But some locations can be problematic.

Like what

Given two short strings for \ (gre\) and \ (eat\), long strings for \ (great\)

Then our long string to become \ (*****\)

Therefore, the differential is introduced.

If the match is on, we are directly to its left and right endpoint \ (+1\) differential.

In the final enumeration, the direct judgment has no tag, if any, then change the current position to \ (*\)

Then direct output can be.

`代码`

``#include <cstdio> #include <cctype> #include <cstring> #define R registerusing namespace Std;char sta[    150008],stb[150008];int pos[150008],k,n,len;struct cod{int nex[55],len; Char s[55];}    Str[55];char st[55],c;inline Char ch (char s) {if (!isalpha (s)) return s;    if (s<= ' Z ' and s>= ' a ') s=s-' a ' + ' a '; return s;}    int main () {scanf ("%d", &n);        for (R int i=1;i<=n;i++) {scanf ("%s", st+1);        Str[i].len=strlen (st+1);        for (R int j=1;j<=str[i].len;j++) str[i].s[j]=ch (St[j]);        str[i].nex[1]=0;k=0;            for (R int j=2;j<=str[i].len;j++) {while (Str[i].s[k+1]!=str[i].s[j] and k) k=str[i].nex[k];            if (Str[i].s[k+1]==str[i].s[j]) k++;        Str[i].nex[j]=k;    }} getchar ();        while (c!= ' \ n ') {C=getchar ();        if (c== ' \ n ') break;        Sta[++len]=c;    Stb[len]=ch (c);        } for (R int i=1;i<=n;i++) {k=0;    for (R int j=1;j<=len;j++) {        while (K and Str[i].s[k+1]!=stb[j]) k=str[i].nex[k];            if (Str[i].s[k+1]==stb[j]) k++;                if (K==str[i].len) {pos[j-str[i].len+1]++;            pos[j+1]--;        }}} for (R int i=1;i<=len;i++) {pos[i]+=pos[i-1];        if (Pos[i]) sta[i]= ' * ';    printf ("%c", Sta[i]); }}/*2gre eatgreat britain***** britain*/``

Kmp+ Differential Article filter (filter)

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