Simpsons’ Hidden Talents - HDU 2594（求相同的前缀后缀）

#include<stdio.h>
#include<string.h>

const int MAXN = 1e5+7;
const int oo = 1e9+7;

char a[MAXN], b[MAXN];
int next[MAXN];

void GetNext(char s[], int N)
{
    int i=0, j=-1;
    next[0] = -1;

    while(i < N)
    {
        if(j==-1 || s[i]==s[j])
            next[++i] = ++j;
        else
            j = next[j];
    }
}

int main()
{
    while(scanf("%s%s", a, b) != EOF)
    {
        int N = strlen(a);

        a[N] = ‘*‘, a[N+1] = 0;
        strcat(a, b);
        N = strlen(a);

        GetNext(a, N);

        if(next[N] == 0)
            printf("0\n");
        else
        {
            a[next[N]] = 0;
            printf("%s %d\n", a, next[N]);
        }
    }

    return 0;
}