题解:
和poj1226差不多
把翻转去掉
然后不要忘记开大数组和二分的上限答案
代码:
#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
const int N=;
char str[N];
int r[N],len,n,t,Index[N],Rank[N],height[N],sa[N],wa[N],wb[N],wv[N],WS[N];
int cmp(int *r,int a,int b,int l)
{
return r[a]==r[b]&&r[a+l]==r[b+l];
}
void da(int *r,int *sa,int n,int m)
{
int p,*x=wa,*y=wb,*t;
for (int i=;i<m;i++)WS[i]=;
for (int i=;i<n;i++)WS[x[i]=r[i]]++;
for (int i=;i<m;i++)WS[i]+=WS[i-];
for (int i=n-;i>=;i--)sa[--WS[x[i]]]=i;
for (int j=,p=;p<n;j*=,m=p)
{
p=;
for (int i=n-j;i<n;i++)y[p++]=i;
for (int i=;i<n;i++)
if (sa[i]>=j)y[p++]=sa[i]-j;
for (int i=;i<n;i++)wv[i]=x[y[i]];
for (int i=;i<m;i++)WS[i]=;
for (int i=;i<n;i++)WS[wv[i]]++;
for (int i=;i<m;i++)WS[i]+=WS[i-];
for (int i=n-;i>=;i--)sa[--WS[wv[i]]]=y[i];
t=x,x=y,y=t,p=,x[sa[]]=;
for (int i=;i<n;i++)
x[sa[i]]=cmp(y,sa[i-],sa[i],j)?p-:p++;
}
return;
}
void calheight(int *r,int *sa,int n)
{
int k=;
for (int i=;i<=n;i++)Rank[sa[i]]=i;
for (int i=;i<n;height[Rank[i++]]=k)
{
k?k--:;
for (int j=sa[Rank[i]-];r[i+k]==r[j+k];k++);
}
return;
}
int check(int x)
{
set<int>se;
for (int i=;i<len;i++)
{
if (height[i]>=x)
{
se.insert(Index[sa[i]]);
se.insert(Index[sa[i-]]);
}
else
{
if (se.size()==n)return ;
se.clear();
}
}
if (se.size()==n)return ;
return false;
}
void solve()
{
int L=,R=,ans=;
while (R>=L)
{
int mid=(L+R)/;
if (check(mid))
{
ans=mid;
L=mid+;
}
else R=mid-;
}
printf("%d\n",ans);
}
int main()
{
scanf("%d",&n);
for (int i=,val=;i<=n;i++)
{
scanf("%s",&str);
for (int j=;j<strlen(str);j++)
{
Index[len]=i;
r[len++]=(str[j]-'a'+*n+);
}
Index[len]=i;
r[len++]=val++;
}
da(r,sa,len,);
calheight(r,sa,len-);
solve();
return ;
}