oj.uz

Submission #924826

# Submission time Handle Problem Language Result Execution time Memory
924826 2024-02-09T19:56:23 Z arneves Palindromes (APIO14_palindrome) C++17
73 / 100
 566 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);
	
	vector<set<ll>> vv(MX);
	vector<ll> count(MX, 0);
	
	ll cur=0;
	
	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].find(u)!=vv[s].end()) 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, count[s]*(2ll*st.A[s].sdep-(1ll-par)));
	};
	
	dfs(dfs, 0, 0);
	
	vv.assign(MX, set<ll>());
	count.assign(MX, 0);
	
	dfs(dfs, 0, 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 21 ms 66136 KB Output is correct
2 Correct 21 ms 66140 KB Output is correct
3 Correct 20 ms 66136 KB Output is correct
4 Correct 21 ms 66136 KB Output is correct
5 Correct 20 ms 66140 KB Output is correct
6 Correct 20 ms 66140 KB Output is correct
7 Correct 20 ms 66140 KB Output is correct
8 Correct 21 ms 66172 KB Output is correct
9 Correct 21 ms 66228 KB Output is correct
10 Correct 20 ms 66140 KB Output is correct
11 Correct 20 ms 66224 KB Output is correct
12 Correct 23 ms 66136 KB Output is correct
13 Correct 20 ms 66276 KB Output is correct
14 Correct 20 ms 66140 KB Output is correct
15 Correct 20 ms 66392 KB Output is correct
16 Correct 21 ms 66396 KB Output is correct
17 Correct 20 ms 66136 KB Output is correct
18 Correct 21 ms 66140 KB Output is correct
19 Correct 20 ms 66140 KB Output is correct
20 Correct 21 ms 66136 KB Output is correct
21 Correct 20 ms 66140 KB Output is correct
22 Correct 21 ms 66136 KB Output is correct
23 Correct 21 ms 66060 KB Output is correct
24 Correct 22 ms 66136 KB Output is correct
25 Correct 21 ms 66256 KB Output is correct
26 Correct 21 ms 66140 KB Output is correct
27 Correct 21 ms 66140 KB Output is correct
28 Correct 20 ms 66028 KB Output is correct
29 Correct 21 ms 66140 KB Output is correct
30 Correct 21 ms 66140 KB Output is correct
31 Correct 23 ms 66136 KB Output is correct
32 Correct 23 ms 66332 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 23 ms 66396 KB Output is correct
2 Correct 22 ms 66396 KB Output is correct
3 Correct 22 ms 66396 KB Output is correct
4 Correct 22 ms 66396 KB Output is correct
5 Correct 22 ms 66396 KB Output is correct
6 Correct 24 ms 66532 KB Output is correct
7 Correct 23 ms 66396 KB Output is correct
8 Correct 22 ms 66396 KB Output is correct
9 Correct 23 ms 66396 KB Output is correct
10 Correct 23 ms 66140 KB Output is correct
11 Correct 23 ms 66136 KB Output is correct
12 Correct 23 ms 66424 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 33 ms 69724 KB Output is correct
2 Correct 32 ms 68548 KB Output is correct
3 Correct 31 ms 71004 KB Output is correct
4 Correct 31 ms 69980 KB Output is correct
5 Correct 56 ms 70220 KB Output is correct
6 Correct 48 ms 69748 KB Output is correct
7 Correct 34 ms 70388 KB Output is correct
8 Correct 43 ms 67336 KB Output is correct
9 Correct 43 ms 67408 KB Output is correct
10 Correct 56 ms 68248 KB Output is correct

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 179 ms 102848 KB Output is correct
2 Correct 158 ms 91264 KB Output is correct
3 Correct 149 ms 98708 KB Output is correct
4 Correct 140 ms 91248 KB Output is correct
5 Correct 540 ms 91896 KB Output is correct
6 Correct 449 ms 91204 KB Output is correct
7 Correct 226 ms 85376 KB Output is correct
8 Correct 349 ms 81068 KB Output is correct
9 Correct 288 ms 81636 KB Output is correct
10 Correct 566 ms 90428 KB Output is correct

Subtask #5
0 / 27.0

# Verdict Execution time Memory Grader output
1 Runtime error 73 ms 131072 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -