解题思路:
求相同的前缀和后缀。开一个数组保存到i位置,模式串有多少个字符和文本串匹配即可。
#include <iostream>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <vector>
#include <queue>
#include <stack>
#define LL long long
#define FOR(i,x,y) for(int i=x;i<=y;i++)
using namespace std;
const int maxn = 100000 + 10;
char s[maxn], t[maxn];
int c[maxn];
int next[maxn];
void get_next()
{
    int m = strlen(s);
    next[0] = 0; next[1] = 0;
    for(int i=1;i<m;i++)
    {
        int j = next[i];
        while(j && s[i] != s[j]) j = next[j];
        next[i+1] = (s[i] == s[j]) ? j + 1 : 0;
    }
}
int KMP()
{
    int n = strlen(t), m = strlen(s);
    get_next();
    int j = 0;
    for(int i=0;i<n;i++)
    {
        while(j && s[j] != t[i]) j = next[j];
        if(s[j] == t[i]) j++;
        c[i] = j;
    }
}
int main()
{
    while(scanf("%s", s)!=EOF)
    {
        scanf("%s", t);
        KMP();
        int n = strlen(t);
        if(c[n-1] == 0) printf("0\n");
        else
        {
            for(int i=0;i<c[n-1];i++)
                printf("%c", s[i]);
            printf(" %d\n", c[n-1]);
        }
    }
    return 0;
}
HDU 2594 Simpsons’ Hidden Talents(KMP)
原文地址:http://blog.csdn.net/moguxiaozhe/article/details/43447575