地址:http://acm.fzu.edu.cn/problem.php?pid=1901
题目:
Problem 1901 Period II
Accept: 442 Submit: 1099
Time Limit: 1000 mSec Memory Limit : 32768 KB
Problem Description
For each prefix with length P of a given string S,if
S[i]=S[i+P] for i in [0..SIZE(S)-p-1],
then the prefix is a “period” of S. We want to all the periodic prefixs.
Input
Input contains multiple cases.
The first line contains an integer T representing the number of cases. Then following T cases.
Each test case contains a string S (1 <= SIZE(S) <= 1000000),represents the title.S consists of lowercase ,uppercase letter.
Output
For each test case, first output one line containing "Case #x: y", where x is the case number (starting from 1) and y is the number of periodic prefixs.Then output the lengths of the periodic prefixs in ascending order.
Sample Input
4
ooo
acmacmacmacmacma
fzufzufzuf
stostootssto
ooo
acmacmacmacmacma
fzufzufzuf
stostootssto
Sample Output
Case #1: 3
1 2 3
Case #2: 6
3 6 9 12 15 16
Case #3: 4
3 6 9 10
Case #4: 2
9 12
1 2 3
Case #2: 6
3 6 9 12 15 16
Case #3: 4
3 6 9 10
Case #4: 2
9 12
Source
FOJ有奖月赛-2010年05月
思路:next数组
#include <cstdio>
#include <cstring>
#include <iostream>
#include <set>
#include <string>
using namespace std; #define MP make_pair
#define PB push_back
typedef long long LL;
const double eps=1e-;
const int K=1e6+;
const int mod=1e9+; int nt[K],ans[K];
char sa[K];
void kmp_next(char *T,int *next)
{
next[]=;
for(int i=,j=,len=strlen(T);i<len;i++)
{
while(j&&T[i]!=T[j]) j=next[j-];
if(T[i]==T[j]) j++;
next[i]=j;
}
}
int kmp(char *S,char *T,int *next)
{
int ans=;
int ls=strlen(S),lt=strlen(T);
for(int i=,j=;i<ls;i++)
{
while(j&&S[i]!=T[j]) j=next[j-];
if(S[i]==T[j]) j++;
if(j==lt) ans++;
}
return ans;
} int main(void)
{
int t,cnt=;cin>>t;
while(t--)
{
scanf("%s",sa);
kmp_next(sa,nt);
int len=strlen(sa),k=;
int tk=len;
while(nt[tk-]>)
ans[k++]=len-nt[tk-],tk=nt[tk-];
ans[k++]=len;
printf("Case #%d: %d\n",cnt++,k);
for(int i=;i<k;i++)
printf("%d%c",ans[i],i!=k-?' ':'\n');
}
return ;
}