P4081 [USACO17DEC]Standing Out from the Herd P

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给定字符串集合，求只属于该字符串的本质不同的非空子串的个数。

广义SAM，插入的时候记录每个初始结点对应的$i$个字符串。向上跑$link$，如果遇到$endpos$里包含其他不属于$i$字符串。标记一下$-1$，并且往后都无效。如果遇到$-1$，表示后面已经标记为$-1$了。不用继续标记。最多标记$|S|$次。最后遍历一遍合法$endpos$即可

代码 
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#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define pii pair<int, int>
#define mk make_pair
const int N = 1e6 + 10;
const int mod = 1e9 + 7;

const int SN = 2e6 + 10;
const int SM = 26;
int vis[SN];
struct SAM
{
    int trans[SN][SM], link[SN], maxlen[SN], pre, scnt;
    SAM() { pre = scnt = 1; }
    void insert(int id)
    {
        int cur = ++scnt;
        maxlen[cur] = maxlen[pre] + 1;
        int u = pre;
        pre = cur;
        for (; u && !trans[u][id]; u = link[u])
            trans[u][id] = cur;
        if (!u)
            link[cur] = 1;
        else
        {
            int x = trans[u][id];
            if (maxlen[x] == maxlen[u] + 1)
                link[cur] = x;
            else
            {
                int nc = ++scnt;
                maxlen[nc] = maxlen[u] + 1;
                link[nc] = link[x];
                link[cur] = link[x] = nc;
                memcpy(trans[nc], trans[x], sizeof(trans[x]));
                for (; u && trans[u][id] == x; u = link[u])
                    trans[u][id] = nc;
            }
        }
        // pre = cur;
    }
    void update(int u, int p)
    {
        for (; u && vis[u] != -1 && vis[u] != p; u = link[u])
        {
            if (vis[u] > 0)
                vis[u] = -1;
            else
                vis[u] = p;
        }
    }
} sam;
ll ans[SN];
int n, len[N];
char t[N], s[N];
int tot;
int main()
{
    scanf("%d", &n);
    for (int i = 1; i <= n; i++)
    {
        sam.pre = 1;
        scanf("%s", t);
        len[i] = strlen(t);
        for (int j = 0; j < len[i]; j++)
            s[++tot] = t[j], sam.insert(t[j] - 'a');
    }
    tot = 0;
    for (int i = 1; i <= n; i++)
    {
        int u = 1;
        for (int j = 0; j < len[i]; j++)
        {
            u = sam.trans[u][s[++tot] - 'a'];
            sam.update(u, i);
        }
    }
    for (int i = 2; i <= sam.scnt; i++)
        ans[vis[i]] += sam.maxlen[i] - sam.maxlen[sam.link[i]];
    for (int i = 1; i <= n; i++)
        printf("%lld\n", ans[i]);
}