Simpsons’ Hidden Talents +KMP

Simpsons’ Hidden Talents

Time Limit : 2000/1000ms (Java/Other)   Memory Limit : 32768/32768K (Java/Other)

Total Submission(s) : 56   Accepted Submission(s) : 17

Problem Description

Homer: Marge, I just figured out a way to discover some of the talents we weren’t aware we had.
Marge: Yeah, what is it?
Homer: Take me for example. I want to find out if I have a talent in politics, OK?
Marge: OK.
Homer: So I take some politician’s name, say Clinton, and try to find the length of the longest prefix
in Clinton’s name that is a suffix in my name. That’s how close I am to being a politician like Clinton
Marge: Why on earth choose the longest prefix that is a suffix???
Homer: Well, our talents are deeply hidden within ourselves, Marge.
Marge: So how close are you?
Homer: 0!
Marge: I’m not surprised.
Homer: But you know, you must have some real math talent hidden deep in you.
Marge: How come?
Homer: Riemann and Marjorie gives 3!!!
Marge: Who the heck is Riemann?
Homer: Never mind.
Write a program that, when given strings s1 and s2, finds the longest prefix of s1 that is a suffix of s2.

 

Input

Input consists of two lines. The first line contains s1 and the second line contains s2. You may assume all letters are in lowercase.

 

Output

Output consists of a single line that contains the longest string that is a prefix of s1 and a suffix of s2, followed by the length of that prefix. If the longest such string is the empty string, then the output should be 0.
The lengths of s1 and s2 will be at most 50000.

 

Sample Input

clinton homer riemann marjorie

 

Sample Output

0 rie 3

/*
题目大意：给你两个字符串，要你求第一个字符串的前缀是第二个字符串的后缀
的最长序列是多少？
思路：用a[]去与b[]匹配，并取最大值（其中有控制j<=lena&&i==lenb）
j<=lena控制a[]完全被b[]包含，i==lena保证是b[]的后缀，刚开始没看清楚是后缀，
wa了n次

*/
#include
#include
using namespace std ;
#define MAX 50005 
int next[MAX],m,n;
char a[MAX] , b[MAX] ;
void pre_next(int k )
{
	int i = 0 , j = -1 ;
	next[0] = - 1 ;
	while( i < k )
	{
		if( j == -1 || a[i] == a[j])
		{
			i++ ;
			j++ ;
			next[i] = j ;
		}
		else
			j = next[j] ;
	}
}

int  KMP()
{
	int max = 0 , k =0 ;
	int i = 0 , j = 0  ;
	int lenb= strlen(b);
	int lena=strlen(a);
	while( i <= lenb )
	{
		if(j== - 1 || a[j]==b[i]){
			i++;
			j++ ;
		}
		else
			j = next[j] ;
		if(max