hdu 2594(kmp)

/*
*      KMP
*      思路：把两个串连接，然后求next[]数组值
*      注意：当两个串都是重复串且重复子串一样是，要特殊处理
*/

#include <cstdio>
#include <iostream>

using namespace std;

const int N = 50005;

int next[N<<1];
char str[N<<1], pat[N];

void indexNext() {
    int k = 0;
    next[1] = 0;
    for (int i=2; str[i]; ++i) {
        while (k && str[k+1]!=str[i]) k = next[k];
        if (str[k+1] == str[i]) ++k;
        next[i] = k;
    } 
}

void solve() {
    int lenPat = strlen(pat);
    int lenStr = strlen(str);
    int len = lenStr + lenPat - 1;
    for (int i=1; i<lenPat; ++i) str[lenStr+i-1] = pat[i];
    str[len] = '\0';
    indexNext();
    if ((len-1)%(len-next[len-1]-1)==0 && next[len-1]!=0) {//特殊处理的数据
        if (lenStr > lenPat) lenStr = lenPat;
        for (int i=1; i<lenStr; ++i) printf ("%c", str[i]);
        printf (" %d\n", lenStr-1);
    }
    else if (next[len-1] == 0) printf ("0\n");
    else {
        for (int i=1; i<=next[len-1]; ++i) printf ("%c", str[i]);
        printf (" %d\n", next[len-1]);
    }
}

int main() {
    str[0] = pat[0] = '#';
    while (scanf("%s%s", str+1, pat+1) != EOF) {
        solve();
    }
    return 0;
}