POJ 2406 Power Strings KMP

题目地址： http://poj.org/problem?id=2406

简单KMP————

AC代码：

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <string>
#include <vector>
#include <list>
#include <deque>
#include <queue>
#include <iterator>
#include <stack>
#include <map>
#include <set>
#include <algorithm>
#include <cctype>
using namespace std;

typedef long long LL;
const int N=1000009;
const LL II=100000000;
const int INF=0x3f3f3f3f;
const double PI=acos(-1.0);

int next[N],tlen,wlen;
char word[N];

void getnext(char *p)
{
    int j=0,k=-1;
    next[0]=-1;
    while(j<wlen)
    {
        if(k==-1||p[j]==p[k])
        {
            j++;    k++;
            next[j]=k;
        }
        else
            k=next[k];
    }
}

int main()
{
    int i,j,T;
    while(scanf("%s",word)&&strcmp(word,".")!=0)
    {
        wlen=strlen(word);
        getnext(word);
        int k=(wlen-next[wlen]);
        if(wlen%k==0)
            printf("%d\n",wlen/k);
        else
            printf("1\n");
    }
    return 0;
}