oj.uz

Submission #924862

# Submission time Handle Problem Language Result Execution time Memory
924862 2024-02-10T00:13:12 Z arneves Palindromes (APIO14_palindrome) C++17
73 / 100
 674 ms 131072 KB 
/*
           ______  _____  _______ _     _ _______ __   _  _____  _  _  _
          |_____/ |     | |       |____/  |______ | \  | |     | |  |  |
          |    \_ |_____| |_____  |    \_ ______| |  \_| |_____| |__|__|
        
        
                   .      .           .      .           .      .    
                   _\/  \/_           _\/  \/_           _\/  \/_    
                    _\/\/_             _\/\/_             _\/\/_     
                _\_\_\/\/_/_/_     _\_\_\/\/_/_/_     _\_\_\/\/_/_/_ 
                 / /_/\/\_\ \       / /_/\/\_\ \       / /_/\/\_\ \  
                    _/\/\_             _/\/\_             _/\/\_     
                    /\  /\             /\  /\             /\  /\     
                   '      '           '      '           '      '    
        
*/

#pragma GCC optimize ("Ofast")
#pragma GCC target ("avx2")
 
#include <bits/stdc++.h>
 
using namespace std;
using ll = long long;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

typedef pair<int, int> pii;
typedef vector<int> vi;
#define pb push_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()
#define f first
#define s second
#define rep(i, a, b) for(int i = a; i < (b); ++i)

void banana(string nome=""){
	cin.tie(0); ios_base::sync_with_stdio(0);
	cout<<fixed<<setprecision(12);
	if(nome.size()){
		freopen((nome+".txt").c_str(),"r",stdin);
		freopen((nome+"_in"+".txt").c_str(),"w",stdout);
	}
}

string yon(ll ans){
	return ans?"YES":"NO";
}

#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//#include <ext/pb_ds/priority_queue.hpp>

const int MX=1200010;

struct SuffixTree{
	
	struct node {
		int head; /**< The path-label start at &(Ti[head]) */
		int sdep; /**< String-Depth, from the root down to node */
		node* child; /**< First child */
		node* brother; /**< Brother */
		node* slink; /**< Suffix-Link */
		node** hook; /**< What keeps this node linked? */
	};
	
	int a;
	node* A;
	
	int ptr2loc(node* v, node* x){
		int r;
		r = -1;
		if(NULL != v) r = ((size_t) v - (size_t) x) / sizeof(struct node);
		return (int)r;
	}
	
	void shownode(node* v) {
		if(NULL == v){
			printf("NULL\n");
		}else{
			printf("node: %d ", ptr2loc(v, A));
			printf("head: %d ", v->head);
			printf("sdep: %d ", v->sdep);
			printf("child: %d ", ptr2loc(v->child, A));
			printf("brother: %d ", ptr2loc(v->brother, A));
			printf("slink: %d", ptr2loc(v->slink, A));
			printf("\n");
		}
	}
	
	struct point {
		node* a; /**< node above */
		node* b; /**< node bellow */
		int s; /**< String-Depth */
	};
	
	int n;
	string T;
	
	int DescendQ(point* p, char c){
		if(p->s==-1) return 1; /* sentinel */
		else if(p->a==p->b){
			/* look for next node */
			node* y=p->b->child;
			
			while(y!=NULL && T[y->head+p->s]!=c) y=y->brother;
			
			if(y==NULL) return 0;
			else return 1;
			
		}else{
			/*descend on edge*/
			if(T[p->b->head+p->s]==c) return 1;
			else return 0;
		}
	}
	
	void Descend(point* p, char c){
		if(p->s==-1){
			/* sentinel */
			p->a=&A[0];
			p->b=&A[0];
			p->s=0;
		}else if(p->b->sdep==p->s){
			/* look for next node */
			node* y=p->b->child;
			while(y!=NULL && T[y->head+p->s]!=c) y=y->brother;
			
			p->a=p->b;
			p->b=y;
			p->s++;
			if(p->s==p->b->sdep) p->a=p->b;
			
		}else{
			/*descend on edge*/
			p->s++;
			if(p->s==p->b->sdep) p->a=p->b;
		}
	}
	
	void add_connection(node* u, node* v){
		/* connect v as child of u */
		if(u->child==NULL){
			u->child=v;
			v->hook=&(u->child);
		}else{
			v->brother=u->child;
			u->child->hook=&(v->brother);
			u->child=v;
			v->hook=&(u->child);
		}
	}
	
	void split(node* u, node* v, int s){
		/* split edge to node u with sdep s and add node v at this position*/
		v->head=u->head;
		v->sdep=s;
		
		if(u->brother!=NULL){
			v->brother=u->brother;
			u->brother->hook=&(v->brother);
		}else{
			v->brother=NULL;
		}
		u->brother=NULL;
		v->child=u;
		*(u->hook)=v;
		v->hook=u->hook;
		u->hook=&(v->child);
	}
		
	node* last;
	
	int AddLeaf(point* p, int i){
		if(p->b==p->a){
			/* add leaf */
			A[a].sdep=n-i+p->s;
			A[a].head=i-p->s;
			add_connection(p->b, &A[a]);
			//printf("Leaf ");
			//shownode(&A[a]);
			return 1;
			
		}else{
			/* split */
			split(p->b, &A[a], p->s);
			
			//printf("Internal ");
			//shownode(&A[a]);
			
			last=&A[a];
			
			/* add leaf */
			A[a+1].sdep=n-i+p->s;
			A[a+1].head=i-p->s;
			add_connection(&A[a], &A[a+1]);
			//printf("Leaf ");
			//shownode(&A[a+1]);
			return 2;
		}
	}
	
	void SuffixLink(point* p){
		/*printf("Begin SL a: %d b: %d s: %d\n",
				ptr2loc(p->a, A), ptr2loc(p->b, A), p->s);*/
		
		node* cur, *y;
		int s, head;
		
		cur=p->a->slink;
		
		s=p->s-1;
		head=p->b->head;
		
		p->a=cur;
		p->b=cur;
		p->s=cur->sdep;
		
		while(p->s<s){
			/*
			printf("a: %d\n",ptr2loc(p->a, A));
			printf("b: %d\n",ptr2loc(p->b, A));
			printf("s: %d\n",p->s);*/
			
			if(p->b==&A[1]){ /* sentinel */
				p->a=p->b=&A[0];
				p->s=0;
			}else{
				y=p->b->child;
				
				while(y!=NULL && T[y->head+p->s]!=T[head+p->s+1]) y=y->brother;
				if(y->sdep<=s){
					p->a=p->b=y;
					p->s=y->sdep;
				}else{
					p->b=y;
					p->s=s;
				}
			}
		}
		
		if(last!=NULL){
			if(p->a==p->b){
				last->slink=p->a;
			}else last->slink=&A[a];
			last=NULL;
		}
		
		/*printf("End SL a: %d b: %d s: %d\n",
				ptr2loc(p->a, A), ptr2loc(p->b, A), p->s);*/
	}
	
	SuffixTree(string str){
		int i;
		point* p=(point*)malloc(sizeof(struct point));
		T=str;
		n=T.size();
		
		A=(node*)calloc(MX, sizeof(struct node));
		p->a=&A[0];
		p->b=&A[0];
		p->s=0;
		
		/* root */
		A[0].head=0;
		A[0].sdep=0;
		A[0].slink=&A[1];
		A[0].hook=&A[1].child;
		
		/* sentinel */
		A[1].head=0;
		A[1].sdep=-1;
		A[1].child=&A[0];
		
		a=2;
		i=0;
		last=NULL;
		
		while(i<n){
			while(!DescendQ(p, T[i])){
				a+=AddLeaf(p, i);
				SuffixLink(p);
			}
			
			Descend(p, T[i]);
			i++;
		}
		
		free(p);
	}
	
	~SuffixTree(){
		free(A);
	}
};

void caso_teste(){
	
	string str; cin>>str;
	ll n=str.size();
	string rev=str;
	reverse(all(rev));
	str+=((char)('a'+26));
	str+=rev;
	str+=((char)('a'+27));
	
	SuffixTree st(str);
	
	set<int> vv[MX];
	vector<int> count(MX, 0);
	
	ll cur=0;
	
	auto work=[&](int par) -> void {
		
		vector<int> mem(MX);
		mem[0]=0;
		int p=0, pp=0;
		
		while(p<=pp){
			int s=mem[p];
			SuffixTree::node* y=st.A[s].child;
			while(y!=NULL){
				//str_depth[y]=str_depth[s]+st.r[y]-st.l[y];
				int yi=st.ptr2loc(y, st.A);
				pp++;
				mem[pp]=yi;
				y=y->brother;
			}
			p++;
		}
		p--;
		while(p>=0){
			int s=mem[p];
			int leaf=0;
			if(st.A[s].child==NULL) leaf=1;
			if(leaf){
				//assert(str[st.r[s]-1]==((char)('a'+27)));
				int k=st.A[s].sdep;
				if(k!=1 && k!=n+2){
					if(k<n+2) k-=2;
					else k-=(n+3), k=n-k-1-par;
					vv[s].insert(k);
				}
			}else{
				SuffixTree::node* y=st.A[s].child;
				while(y!=NULL){
					//str_depth[y]=str_depth[s]+st.r[y]-st.l[y];
					int yi=st.ptr2loc(y, st.A);
					count[s]+=count[yi];
					if(vv[yi].size()>vv[s].size()) swap(vv[yi], vv[s]);
					
					for(int u: vv[yi]){
						if(vv[s].count(u)==1) vv[s].erase(u), count[s]++;
						else vv[s].insert(u);
					}
					
					vv[yi].clear();
					y=y->brother;
				}
			}
			cur=max(cur, ((ll)count[s])*(2ll*((ll)st.A[s].sdep)-(1ll-par)));
			p--;
		}
	};
	
	/*
	auto dfs = [&](auto&& self, int s, ll par) -> void {
		int leaf=0;
		if(st.A[s].child==NULL) leaf=1;
		if(leaf){
			//assert(str[st.r[s]-1]==((char)('a'+27)));
			int k=st.A[s].sdep;
			if(k!=1 && k!=n+2){
				if(k<n+2) k-=2;
				else k-=(n+3), k=n-k-1-par;
				vv[s].insert(k);
			}
		}else{
			SuffixTree::node* y=st.A[s].child;
			while(y!=NULL){
				
				//str_depth[y]=str_depth[s]+st.r[y]-st.l[y];
				int yi=st.ptr2loc(y, st.A);
				self(self, yi, par);
				count[s]+=count[yi];
				if(vv[yi].size()>vv[s].size()) swap(vv[yi], vv[s]);
				
				for(int u: vv[yi]){
					if(vv[s].count(u)==1) vv[s].erase(u), count[s]++;
					else vv[s].insert(u);
				}
				
				vv[yi].clear();
				y=y->brother;
			}
		}
		//cout<<s<<' '<<leaf<<' '<<count[s]<<' '<<st.A[s].sdep<<endl;
		cur=max(cur, ((ll)count[s])*(2ll*((ll)st.A[s].sdep)-(1ll-par)));
	};*/
	
	work(0);
	
	for(int i=0; i<MX; i++) vv[i].clear();
	//for(auto &u: vv) u.clear();
	for(int &u: count) u=0;
	
	work(1);
	
	cout<<cur<<'\n';
}

int main(){
	
	banana();
	
	int n_casos=1; //cin>>n_casos;
	
	while(n_casos--) caso_teste();
}

Compilation message

palindrome.cpp: In function 'void banana(std::string)':
palindrome.cpp:41:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |   freopen((nome+".txt").c_str(),"r",stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
palindrome.cpp:42:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |   freopen((nome+"_in"+".txt").c_str(),"w",stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 48 ms 66132 KB Output is correct
2 Correct 47 ms 66132 KB Output is correct
3 Correct 48 ms 66128 KB Output is correct
4 Correct 46 ms 66156 KB Output is correct
5 Correct 47 ms 66060 KB Output is correct
6 Correct 49 ms 66132 KB Output is correct
7 Correct 47 ms 66140 KB Output is correct
8 Correct 47 ms 66112 KB Output is correct
9 Correct 51 ms 66128 KB Output is correct
10 Correct 48 ms 66200 KB Output is correct
11 Correct 47 ms 66128 KB Output is correct
12 Correct 47 ms 66132 KB Output is correct
13 Correct 48 ms 66132 KB Output is correct
14 Correct 49 ms 66396 KB Output is correct
15 Correct 47 ms 66132 KB Output is correct
16 Correct 48 ms 66200 KB Output is correct
17 Correct 48 ms 66140 KB Output is correct
18 Correct 48 ms 66128 KB Output is correct
19 Correct 47 ms 66128 KB Output is correct
20 Correct 48 ms 66132 KB Output is correct
21 Correct 49 ms 66132 KB Output is correct
22 Correct 46 ms 66128 KB Output is correct
23 Correct 47 ms 66144 KB Output is correct
24 Correct 46 ms 66140 KB Output is correct
25 Correct 47 ms 66132 KB Output is correct
26 Correct 47 ms 66132 KB Output is correct
27 Correct 48 ms 66136 KB Output is correct
28 Correct 46 ms 66140 KB Output is correct
29 Correct 49 ms 66140 KB Output is correct
30 Correct 47 ms 66136 KB Output is correct
31 Correct 47 ms 66212 KB Output is correct
32 Correct 49 ms 66180 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 49 ms 66384 KB Output is correct
2 Correct 48 ms 66392 KB Output is correct
3 Correct 49 ms 66312 KB Output is correct
4 Correct 48 ms 66396 KB Output is correct
5 Correct 50 ms 66288 KB Output is correct
6 Correct 48 ms 66396 KB Output is correct
7 Correct 50 ms 66432 KB Output is correct
8 Correct 49 ms 66396 KB Output is correct
9 Correct 49 ms 66384 KB Output is correct
10 Correct 49 ms 66384 KB Output is correct
11 Correct 52 ms 66404 KB Output is correct
12 Correct 50 ms 66452 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 65 ms 69380 KB Output is correct
2 Correct 60 ms 70404 KB Output is correct
3 Correct 58 ms 69032 KB Output is correct
4 Correct 57 ms 69712 KB Output is correct
5 Correct 81 ms 68540 KB Output is correct
6 Correct 75 ms 68352 KB Output is correct
7 Correct 61 ms 69804 KB Output is correct
8 Correct 72 ms 69596 KB Output is correct
9 Correct 74 ms 69512 KB Output is correct
10 Correct 83 ms 69532 KB Output is correct

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 214 ms 92748 KB Output is correct
2 Correct 187 ms 91192 KB Output is correct
3 Correct 156 ms 83852 KB Output is correct
4 Correct 152 ms 81984 KB Output is correct
5 Correct 607 ms 92584 KB Output is correct
6 Correct 439 ms 93268 KB Output is correct
7 Correct 245 ms 84536 KB Output is correct
8 Correct 482 ms 86956 KB Output is correct
9 Correct 365 ms 86156 KB Output is correct
10 Correct 674 ms 92424 KB Output is correct

Subtask #5
0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 498 ms 131072 KB Output is correct
2 Runtime error 441 ms 131072 KB Execution killed with signal 9
3 Halted 0 ms 0 KB -