来一份模板
1 #include<cstdio>
2 #include<algorithm>
3 #include<cstring>
4 #include<queue>
5 using namespace std;
6 typedef long long LL;
7 char s[1000100];
8 int n;
9 LL ans;
10 namespace SAM
11 {
12 int mem,np,root;
13 int len[2000100],par[2000100];
14 int trans[2000100][26];
15 int in[2000100],sz[2000100];
16 void append(int ch)
17 {
18 int p=np;np=++mem;len[np]=len[p]+1;
19 for(;p&&!trans[p][ch];p=par[p]) trans[p][ch]=np;
20 if(!p) par[np]=root;
21 else
22 {
23 int q=trans[p][ch];
24 if(len[q]==len[p]+1) par[np]=q;
25 else
26 {
27 int nq=++mem;par[nq]=par[q];par[q]=par[np]=nq;
28 memcpy(trans[nq],trans[q],sizeof(trans[nq]));len[nq]=len[p]+1;
29 for(;p&&trans[p][ch]==q;p=par[p]) trans[p][ch]=nq;
30 }
31 }
32 sz[np]=1;
33 }
34 void build()
35 {
36 np=root=++mem;
37 for(int i=1;i<=n;i++) append(s[i]-‘a‘);
38 }
39 queue<int> q;
40 void work()
41 {
42 int i,t;
43 for(i=1;i<=mem;i++) ++in[par[i]];
44 for(i=1;i<=mem;i++)
45 if(!in[i])
46 q.push(i);
47 while(!q.empty())
48 {
49 t=q.front();q.pop();
50 if(sz[t]>1) ans=max(ans,LL(sz[t])*len[t]);
51 if(par[t])
52 {
53 sz[par[t]]+=sz[t];
54 --in[par[t]];
55 if(!in[par[t]]) q.push(par[t]);
56 }
57 }
58 }
59 }
60
61 int main()
62 {
63 scanf("%s",s+1);n=strlen(s+1);
64 SAM::build();SAM::work();
65 printf("%lld",ans);
66 return 0;
67 }
还有后缀数组强行A此题
1 #pragma GCC optimize("Ofast")
2 #pragma GCC target("sse3","sse2","sse")
3 #pragma GCC target("avx","sse4","sse4.1","sse4.2","ssse3")
4 #pragma GCC target("f16c")
5 #pragma GCC optimize("inline","fast-math","unroll-loops","no-stack-protector")
6 #pragma GCC diagnostic error "-fwhole-program"
7 #pragma GCC diagnostic error "-fcse-skip-blocks"
8 #pragma GCC diagnostic error "-funsafe-loop-optimizations"
9 #pragma GCC diagnostic error "-std=c++14"
10 #include<cstdio>
11 #include<algorithm>
12 #include<cstring>
13 #include<map>
14 using namespace std;
15 char s[1000100];
16 int n;
17 namespace SA
18 {
19 int sa[1000100],t1[1000100],t2[1000100],m=‘z‘,cnt[1000100],p;
20 int *x=t1,*y=t2,*rk=t1,*height=t2;
21 template<typename T>
22 T get(int pos,T *a)
23 {
24 return pos<=n?a[pos]:0;
25 }
26 void build()
27 {
28 int i,k;int *it,*ed;
29 for(i=1;i<=n;++i) ++cnt[x[i]=s[i]];
30 for(it=cnt+1,ed=cnt+m+1;it!=ed;++it) *it+=*(it-1);
31 for(i=n;i>=1;--i) sa[cnt[x[i]]--]=i;
32 for(k=1;k<=n;k<<=1)
33 {
34 p=0;
35 for(i=n-k+1;i<=n;++i) y[++p]=i;
36 for(i=1;i<=n;++i) if(sa[i]>k) y[++p]=sa[i]-k;
37 for(it=cnt+1,ed=cnt+m+1;it!=ed;++it) *it=0;
38 for(i=1;i<=n;++i) cnt[x[y[i]]]++;
39 for(it=cnt+1,ed=cnt+m+1;it!=ed;++it) *it+=*(it-1);
40 for(i=n;i>=1;--i) sa[cnt[x[y[i]]]--]=y[i];
41 swap(x,y);p=0;
42 for(i=1;i<=n;++i)
43 x[sa[i]]=y[sa[i]]==y[sa[i-1]]&&get(sa[i]+k,y)==get(sa[i-1]+k,y)
44 ?p:++p;
45 if(p>=n) break;
46 m=p;
47 }
48 for(i=1;i<=n;++i) rk[sa[i]]=i;
49 for(i=1,k=1;i<=n;++i)
50 {
51 if(k) k--;
52 if(rk[i])
53 while(get(sa[rk[i]-1]+k,s)==get(i+k,s)) k++;
54 height[rk[i]]=k;
55 }
56 }
57 }
58 int sz[1000100],fa[1000100];
59 int find(int x) {return x==fa[x]?x:fa[x]=find(fa[x]);}
60 typedef pair<int,int> P;
61 typedef long long LL;
62 P tmp[1000100];
63 LL ans;
64 bool cmp(const P& a,const P& b)
65 {
66 return a>b;
67 }
68 int main()
69 {
70 int i,d,t,fx,fy;
71 scanf("%s",s+1);n=strlen(s+1);SA::build();
72 for(i=1;i<=n;i++) fa[i]=i,sz[i]=1;
73 for(i=2;i<=n;i++) tmp[i]=P(SA::height[i],i);
74 sort(tmp+2,tmp+n+1,cmp);
75 for(i=2;i<=n;i++)
76 {
77 d=tmp[i].first;t=tmp[i].second;
78 fx=find(t-1);fy=find(t);
79 sz[fy]+=sz[fx];fa[fx]=fy;
80 ans=max(ans,LL(sz[fy])*d);
81 }
82 printf("%lld",ans);
83 return 0;
84 }
以下是作死用map之后T掉的程序
1 #include<cstdio>
2 #include<algorithm>
3 #include<cstring>
4 #include<map>
5 #include<queue>
6 using namespace std;
7 typedef long long LL;
8 char s[1000100];
9 int n;
10 LL ans;
11 namespace SAM
12 {
13 int mem,np,root;
14 int len[2000100],par[2000100];
15 map<int,int> trans[2000100];
16 int in[2000100],sz[2000100];
17 void append(int ch)
18 {
19 int p=np;np=++mem;len[np]=len[p]+1;
20 for(;p&&!trans[p].count(ch);p=par[p]) trans[p][ch]=np;
21 if(!p) par[np]=root;
22 else
23 {
24 int q=trans[p][ch];
25 if(len[q]==len[p]+1) par[np]=q;
26 else
27 {
28 int nq=++mem;par[nq]=par[q];par[q]=par[np]=nq;
29 trans[nq]=trans[q];len[nq]=len[p]+1;
30 for(;p&&trans[p].count(ch)&&trans[p][ch]==q;p=par[p]) trans[p][ch]=nq;
31 }
32 }
33 sz[np]=1;
34 }
35 void build()
36 {
37 np=root=++mem;
38 for(int i=1;i<=n;i++) append(s[i]-‘a‘);
39 }
40 queue<int> q;
41 void work()
42 {
43 int i,t;
44 for(i=1;i<=mem;i++) ++in[par[i]];
45 for(i=1;i<=mem;i++)
46 if(!in[i])
47 q.push(i);
48 while(!q.empty())
49 {
50 t=q.front();q.pop();
51 if(sz[t]>1) ans=max(ans,LL(sz[t])*len[t]);
52 if(par[t])
53 {
54 sz[par[t]]+=sz[t];
55 --in[par[t]];
56 if(!in[par[t]]) q.push(par[t]);
57 }
58 }
59 }
60 }
61
62 int main()
63 {
64 scanf("%s",s+1);n=strlen(s+1);
65 SAM::build();SAM::work();
66 printf("%lld",ans);
67 return 0;
68 }
原文地址：https://www.cnblogs.com/hehe54321/p/8716607.html
时间： 2024-08-30 14:41:28