hdu 4300KMP

这题纯属蹭过，按理说应该是扩展KMP的方法。我是直接用的KMP的next数组，特殊情况加以判断就过了。

/*

 * hdu4300/win.cpp

 * Created on: 2012-8-1

 * Author    : ben

 */

#include <cstdio>

#include <cstdlib>

#include <cstring>

#include <cmath>

#include <ctime>

#include <iostream>

#include <algorithm>

#include <queue>

#include <set>

#include <map>

#include <stack>

#include <string>

#include <vector>

#include <deque>

#include <list>

#include <functional>

#include <numeric>

#include <cctype>

using namespace std;

const int MAX_LEN = 100010;

char swit[128];

char pattern[MAX_LEN];

int next[MAX_LEN], parlen;

char getPlain(char c) {

    for(int i = 'a'; i <= 'z'; i++) {

        if(swit[i] == c) {

            return (char)i;

        }

    }

    return 0;

}

int work() {

    int i = 0, j = -1;

    next[0] = -1;

    while (i < parlen) {

        if (j < 0 || swit[(int)pattern[i]] == pattern[j]) {

            i++;

            j++;

            next[i] = j;

        } else {

            j = next[j];

        }

    }

    if(next[parlen - 1] == 0) {

        if(pattern[0] != swit[(int)pattern[parlen - 1]]) {

            return -1;

        }

    }

    if(next[parlen - 1] < (parlen / 2)) {

        return next[parlen - 1];

    }else {

        int xhj = parlen - next[parlen - 1] - 1;

        int xhs = parlen / xhj;

        if(xhs % 2 == 0) {

            return parlen / 2 - 1;

        }else {

            return (xhs / 2) * xhj - 1;

        }

    }

}



int main() {

#ifndef ONLINE_JUDGE

    freopen("data.in", "r", stdin);

#endif

    int T;

    scanf("%d", &T);

    for(int t = 1; t <= T; t++) {

        char tempstr[200];

        scanf("%s%s", tempstr, pattern);

        parlen = strlen(tempstr);

        for(int i = 'a'; i <= 'z'; i++) {

            swit[i] = tempstr[i - 'a'];

        }

        parlen = strlen(pattern);

        int s = work() + 1;

//        printf("%d\n", s - 1);

        int e = parlen - s;

        printf("%s", pattern);

        for(; s < e; s++) {

            putchar(getPlain(pattern[s]));

        }

        putchar('\n');

    }

    return 0;

}