Submission #1124169

#	Time	Username	Problem	Language	Result	Execution time	Memory
1124169		ljtunas	Izbori (COCI22_izbori)	C++17	110 / 110	1584 ms	11008 KiB

Main

// author : anhtun_hi , nqg
// 25-26.12.2024

#include <bits/stdc++.h>
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define reset(h, v)    memset(h, v, sizeof h)
#define Forv(i, a)     for(auto& i : a)
#define For(i, a, b)   for(int i = a; i <= b; ++i)
#define Ford(i, a, b)  for(int i = a; i >= b; --i)
#define c_bit(i)     __builtin_popcountll(i)
#define Bit(mask, i)    ((mask >> i) & 1LL)
#define onbit(mask, i)  ((mask) bitor (1LL << i))
#define offbit(mask, i) ((mask) &~ (1LL << i))
#define Log2(x) (63 - __builtin_clzll(x))
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
using namespace std;

using ll = long long;
using ii = pair<ll, ll>;
using db = long double;
using ull = unsigned long long;

namespace std {
    template <typename T, int D>
    struct _vector : public vector <_vector <T, D - 1>> {
        static_assert(D >= 1, "Dimension must be positive!");
        template <typename... Args>
        _vector(int n = 0, Args... args) : vector <_vector <T, D - 1>> (n, _vector <T, D - 1> (args...)) {}
    };
    template <typename T> struct _vector <T, 1> : public vector <T> {
        _vector(int n = 0, const T& val = T()) : vector <T> (n, val) {}
    };
    template <class A, class B> bool minimize(A &a, B b){return a > b ? a = b, true : false;}
    template <class A, class B> bool maximize(A &a, B b){return a < b ? a = b, true : false;}
}
const int dx[] = {0, 0, +1, -1}, dy[] = {-1, +1, 0, 0}, LOG = 20, base = 311, inf = 1e9 + 5;
const int MAXN = 2e5 + 5;
const  ll  mod = 1e9 + 7;
const  ll   oo = 1e18;

//#define int long long

int n, a[MAXN], b[MAXN], Block;
vector<int> List[MAXN];
struct Fenwick{
    int bit[MAXN * 2];
    void update(int u, int val){
        u += 2e5+1;
        while(u <= 4e5+5) bit[u] += val, u += u &- u;
    }
    ll get(int u){
        u += 2e5+1;
        ll res = 0;
        while (u) res += bit[u], u -= u &- u;
        return res;
    }
} T;

int cnt[MAXN], f[MAXN];

void Solve() {
    cin >> n; Block = 1000;
    vector<int> compress;
    For(i, 1, n) cin >> a[i], compress.push_back(a[i]);
    sort(all(compress)), compress.resize(unique(all(compress)) - compress.begin());
    For(i, 1, n) {
        a[i] = lower_bound(all(compress), a[i]) - compress.begin() + 1;
        List[a[i]].push_back(i);
    }

    ll ans = 0;
    For(i, 1, n){
        int mx = 0;
        for (int j = i; j <= min(n, i + 2 * Block - 1); ++j){
            if (List[a[j]].size() <= Block) ++cnt[a[j]], maximize(mx, cnt[a[j]]);
            if (mx * 2 > (j - i + 1)) ++ans;//cerr << i << ' ' << j << '\n';
        }
        for (int j = i; j <= min(n, i + 2 * Block - 1); ++j){
            if (List[a[j]].size() <= Block) --cnt[a[j]];
        }
    }
    vector<int> vec;
    For(i, 1, n) if (List[i].size() > Block) vec.push_back(i);
    Forv(u, vec){
        For(i, 1, n) {
            if(a[i] == u) b[i] = 1;
            else b[i] = -1;
        }
        For(i, 1, n) f[i] = f[i - 1] + b[i];//cerr << f[i] << ' '; cerr << '\n';
        For(i, 0, n) ans += T.get(f[i] - 1), T.update(f[i], 1);
        For(i, 0, n) T.update(f[i], -1);
    }
    cout << ans << '\n';
}

signed main() {
    cin.tie(0) -> sync_with_stdio(0);
    if(fopen("a.inp", "r")) {
        freopen("a.inp", "r", stdin);
        freopen("a.out", "w", stdout);
    }

    int t = 1;
//    cin >> t;
    while(t --) Solve();
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:101:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  101 |         freopen("a.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
Main.cpp:102:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  102 |         freopen("a.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 70 / 70