Seek the Name, Seek the Fame （poj2752

Seek the Name, Seek the Fame

Time Limit: 2000MS		Memory Limit: 65536K
Total Submissions: 14561		Accepted: 7288

Description

The little cat is so famous, that many couples tramp over hill and dale to Byteland, and asked the little cat to give names to their newly-born babies. They seek the name, and at the same time seek the fame. In order to escape from such boring job, the innovative little cat works out an easy but fantastic algorithm: 

Step1. Connect the father's name and the mother's name, to a new string S. 
Step2. Find a proper prefix-suffix string of S (which is not only the prefix, but also the suffix of S). 

Example: Father='ala', Mother='la', we have S = 'ala'+'la' = 'alala'. Potential prefix-suffix strings of S are {'a', 'ala', 'alala'}. Given the string S, could you help the little cat to write a program to calculate the length of possible prefix-suffix strings of S? (He might thank you by giving your baby a name:) 

Input

The input contains a number of test cases. Each test case occupies a single line that contains the string S described above. 

Restrictions: Only lowercase letters may appear in the input. 1 <= Length of S <= 400000. 

Output

For each test case, output a single line with integer numbers in increasing order, denoting the possible length of the new baby's name.

Sample Input

ababcababababcabab
aaaaa

Sample Output

2 4 9 18
1 2 3 4 5

Source

POJ Monthly--2006.01.22,Zeyuan Zhu

题意：给一字符串让你找出其前缀和后缀相等的可能长度都是多少，升序输出。

简单模板一遍过

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>

using namespace std;

#define N 400008

char w[N];
int next[N];
int sum[N];

void getNext()
{
    int j, k;
    int i = strlen(w);
    j = 0;
    k = -1;
    next[0] = -1;

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

int main()
{
    while(~scanf("%s", w))
    {
        memset(next, 0, sizeof(next));
        memset(sum, 0, sizeof(sum));

        getNext();
        int l1, k;
        l1 = strlen(w);

        k = 0;
        sum[k++] = l1;

        while(l1 > 1 && next[l1])
        {
            sum[k] = next[l1];
            l1 = sum[k];
            k++;
        }

        sort(sum, sum+k);
        printf("%d", sum[0]);

        for(int i = 1; i < k; i++)
        {
            printf(" %d", sum[i]);
        }

        puts("");
    }
    return 0;
}