poj 2406 Power Strings【kmp】

kmp,根据next数组的性质如果有答案的话就是n/(n-(ne[n]+1)),否则是1
搬来打算用SA后来发现必须用DC3就没写

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int N=1000005;
int n,ne[N];
char s[N];
int main()
{
    while(scanf("%s",s)&&s[0]!='.')
    {
        n=strlen(s);
        ne[0]=-1;
        for(int i=1,j=-1;i<n;i++)
        {
            while(j!=-1&&s[i]!=s[j+1])
                j=ne[j];
            if(s[i]==s[j+1])
                j++;
            ne[i]=j;
        }
        ne[n]=ne[n-1]+1;
        if(n%(n-ne[n])==0)
            printf("%d\n",n/(n-ne[n]));
        else
            puts("1");
    }
    return 0;
}

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转载自www.cnblogs.com/lokiii/p/9990908.html