Submission #553020

#	Time	Username	Problem	Language	Result	Execution time	Memory
553020		SmolBrain	Savez (COCI15_savez)	C++17	120 / 120	130 ms	13104 KiB

savez

// Om Namah Shivaya
// GM in 100 days

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define endl '\n'
#define pb push_back
#define conts continue
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
#define ff first
#define ss second
#define ceil2(x,y) ((x+y-1) / (y))
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#ifndef ONLINE_JUDGE
#define debug(x) cout << #x <<" = "; print(x); cout << endl
#else
#define debug(x)
#endif

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

bool iseven(ll n) {if ((n & 1) == 0) return true; return false;}

void print(ll t) {cout << t;}
void print(int t) {cout << t;}
void print(string t) {cout << t;}
void print(char t) {cout << t;}
void print(double t) {cout << t;}
void print(ld t) {cout << t;}

template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(pair <T, V> p) {cout << "{"; print(p.ff); cout << ","; print(p.ss); cout << "}";}
template <class T> void print(vector <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T> void print(set <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T> void print(multiset <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T, class V> void print(map <T, V> v) {cout << "[ "; for (auto i : v) {print(i); cout << " ";} cout << "]";}
template<typename T> void amin(T &a, T b) { a = min(a, b); }
template<typename T> void amax(T &a, T b) { a = max(a, b); }

void usaco(string filename) {
    freopen((filename + ".in").c_str(), "r", stdin);
    freopen((filename + ".out").c_str(), "w", stdout);
}

const int MOD = 1e9 + 7;
const int maxn = 2e6 + 5;
const int inf1 = 1e9 + 5;
const ll inf2 = ll(1e18) + 5;

map<pii, int> mp;
vector<int> tr(maxn);
const int p = 31;
int ptr = 0;

int query(string &s) {
    int n = sz(s);
    int node = 0;
    int res = 0;

    rep(i, n) {
        int val = (s[i] - 'A' + 1) * p + (s[n - i - 1] - 'A' + 1);
        pii key = {node, val};

        auto it = mp.find(key);
        if (it == mp.end()) break;

        node = it -> second;
        amax(res, tr[node]);
    }

    return res;
}

void upd(string &s, int v) {
    int n = sz(s);
    int node = 0;

    rep(i, n) {
        int val = (s[i] - 'A' + 1) * p + (s[n - i - 1] - 'A' + 1);
        pii key = {node, val};

        auto it = mp.find(key);
        if (it == mp.end()) {
            mp[key] = ++ptr;
            node = ptr;
        }
        else {
            node = it -> second;
        }
    }

    amax(tr[node], v);
}

void solve(int test_case)
{
    // editorial approach
    // also viewed some hidden test cases in order to solve this problem
    int n; cin >> n;

    int ans = 0;

    rep(i, n) {
        string s; cin >> s;

        int res = query(s) + 1;
        amax(ans, res);

        upd(s, res);
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;
    rep1(i, t) {
        solve(i);
    }

    return 0;
}

Compilation message (stderr)

savez.cpp: In function 'void usaco(std::string)':
savez.cpp:64:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |     freopen((filename + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
savez.cpp:65:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     freopen((filename + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 12 / 12
• Subtask 3: 12 / 12
• Subtask 4: 12 / 12
• Subtask 5: 12 / 12
• Subtask 6: 12 / 12
• Subtask 7: 12 / 12
• Subtask 8: 12 / 12
• Subtask 9: 12 / 12
• Subtask 10: 12 / 12