Submission #778029

#	Time	Username	Problem	Language	Result	Execution time	Memory
778029		horiiseun	Palindromes (APIO14_palindrome)	C++17	100 / 100	95 ms	78324 KiB

palindrome

#include <iostream>
#include <vector>
#include <tuple>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <map>
#include <cmath>
#include <random>
#include <string>
#include <bitset>
#include <cassert>
#include <climits>
#include <algorithm>
#include <unordered_set>
#include <unordered_map>
using namespace std;
 
#define ll long long
#define f first
#define s second
 
void __print(int x) { cerr << x; }
void __print(long x) { cerr << x; }
void __print(long long x) { cerr << x; }
void __print(unsigned x) { cerr << x; }
void __print(unsigned long x) { cerr << x; }
void __print(unsigned long long x) { cerr << x; }
void __print(float x) { cerr << x; }
void __print(double x) { cerr << x; }
void __print(long double x) { cerr << x; }
void __print(char x) { cerr << '\'' << x << '\''; }
void __print(const char *x) { cerr << '\"' << x << '\"'; }
void __print(const string &x) { cerr << '\"' << x << '\"'; }
void __print(bool x) { cerr << (x ? "true" : "false"); }
 
template<typename A> void __print(const A &x);
template<typename A, typename B> void __print(const pair<A, B> &p);
template<typename... A> void __print(const tuple<A...> &t);
template<typename T> void __print(stack<T> s);
template<typename T> void __print(queue<T> q);
template<typename T, typename... U> void __print(priority_queue<T, U...> q);
 
template<typename A> void __print(const A &x) {
    bool first = true;
    cerr << '{';
    for (const auto &i : x) {
        cerr << (first ? "" : ","), __print(i);
        first = false;
    }
    cerr << '}';
}
 
template<typename A, typename B> void __print(const pair<A, B> &p) {
    cerr << '(';
    __print(p.f);
    cerr << ',';
    __print(p.s);
    cerr << ')';
}
 
template<typename... A> void __print(const tuple<A...> &t) {
    bool first = true;
    cerr << '(';
    apply([&first] (const auto &...args) { ((cerr << (first ? "" : ","), __print(args), first = false), ...); }, t);
    cerr << ')';
}
 
template<typename T> void __print(stack<T> s) {
    vector<T> debugVector;
    while (!s.empty()) {
        T t = s.top();
        debugVector.push_back(t);
        s.pop();
    }
    reverse(debugVector.begin(), debugVector.end());
    __print(debugVector);
}
 
template<typename T> void __print(queue<T> q) {
    vector<T> debugVector;
    while (!q.empty()) {
        T t = q.front();
        debugVector.push_back(t);
        q.pop();
    }
    __print(debugVector);
}
 
template<typename T, typename... U> void __print(priority_queue<T, U...> q) {
    vector<T> debugVector;
    while (!q.empty()) {
        T t = q.top();
        debugVector.push_back(t);
        q.pop();
    }
    __print(debugVector);
}
 
void _print() { cerr << "]\n"; }
 
template <typename Head, typename... Tail> void _print(const Head &H, const Tail &...T) {
    __print(H);
    if (sizeof...(T)) cerr << ", ";
    _print(T...);
}
 
#ifdef DEBUG
	#define D(...) cerr << "Line: " << __LINE__ << " [" << #__VA_ARGS__ << "] = ["; _print(__VA_ARGS__)
#else
    #define D(...)
#endif
 
struct Node {
	int nxt[30], suffLink;
	ll len, cnt;
	vector<int> edges;
} tree[300005];
 
string s;
int suff, idx;
ll ans;
 
void addLetter(int pos) {
	int curr = suff, currLen = 0, let = s[pos] - 'a';
	while (true) {
		currLen = tree[curr].len;
		if (pos - 1 - currLen >= 0 && s[pos - 1 - currLen] == s[pos]) {
			break;
		}
		curr = tree[curr].suffLink;
	}
	if (tree[curr].nxt[let]) {
		suff = tree[curr].nxt[let];
		tree[suff].cnt++;
		return;
	}
	idx++;
	suff = idx;
	tree[idx].len = tree[curr].len + 2;
	tree[idx].cnt = 1;
	tree[curr].nxt[let] = idx;
	if (tree[idx].len == 1) {
		tree[idx].suffLink = 2;
		tree[2].edges.push_back(idx);
		return;
	}
	while (true) {
		curr = tree[curr].suffLink;
		currLen = tree[curr].len;
		if (pos - 1 - currLen >= 0 && s[pos - 1 - currLen] == s[pos]) {
			tree[idx].suffLink = tree[curr].nxt[let];
			tree[tree[curr].nxt[let]].edges.push_back(idx);
			break;
		}
	}
}
 
void dfs(int curr) {
	for (int i : tree[curr].edges) {
		dfs(i);
		tree[curr].cnt += tree[i].cnt;
	}
	ans = max(ans, tree[curr].cnt * tree[curr].len);
}
 
int main() {
 
	ios_base::sync_with_stdio(false);
	cin.tie(0);
 
	cin >> s;
	idx = 2, suff = 2;
	tree[1].len = -1, tree[1].suffLink = 1;
	tree[2].len = 0, tree[2].suffLink = 1;
	tree[1].edges.push_back(2);
 
	for (int i = 0; i < s.length(); i++) {
		addLetter(i);
	}
	dfs(1);
 
	cout << ans << "\n";
 
}

Compilation message (stderr)

palindrome.cpp: In function 'int main()':
palindrome.cpp:179:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  179 |  for (int i = 0; i < s.length(); i++) {
      |                  ~~^~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 15 / 15
• Subtask 3: 24 / 24
• Subtask 4: 26 / 26
• Subtask 5: 27 / 27