제출 #915011

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
915011		Whisper	K blocks (IZhO14_blocks)	C++14	0 / 100	1 ms	2396 KiB

blocks

#include <bits/stdc++.h>

using namespace std;
using ll = long long;
using ld = long double;
using T = tuple<ll, ll, ll>;

#define int long long
#define Base 41
#define sz(a) (int)a.size()
#define FOR(i, a, b) for ( int i = a ; i <= b ; i++ )
#define FORD(i, a, b) for (int i = b; i >= a; i --)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPD(i, n) for (int i = n - 1; i >= 0; --i)
#define all(x) x.begin() , x.end()
#define pii pair<int , int>
#define fi first
#define se second
#define Lg(x) 31 - __builtin_clz(x)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)

constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int MAX = 2e5 + 5;
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

void setupIO(){
    #define name "Whisper"
    //Phu Trong from Nguyen Tat Thanh High School for gifted student
    srand(time(NULL));
    cin.tie(nullptr)->sync_with_stdio(false); cout.tie(nullptr);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    cout << fixed << setprecision(10);
}

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }

int N, K;
int a[MAX];

vector<int> pre, dp;
const int Log = 18;
int st[MAX][Log];

int cost (int l, int r){
    int k = Lg(r - l + 1);
    return max(st[l][k], st[r - MASK(k) + 1][k]);
}

void solve(int l, int r, int from, int to){
    if (l > r) return;
    int mid = (l + r) >> 1;
    int best = -1;
    dp[mid] = LINF;
    for (int i = from; i <= min(mid, to); ++i){
        int newCost = pre[i] + cost(i + 1, mid);
        if (minimize(dp[mid], newCost)){
            best = i;
        }
    }

    assert(best != -1);
    solve(l, mid - 1, from, best);
    solve(mid + 1, r, best, to);
}
void Whisper(){
    cin >> N >> K;
    for (int i = 1; i <= N; ++i) cin >> a[i];

    for (int i = 1; i <= N; ++i) st[i][0] = a[i];
    for (int k = 1; MASK(k) <= N; ++k){
        for (int i = 1; i + MASK(k) - 1 <= N; ++i){
            st[i][k] = max(st[i][k - 1], st[i + MASK(k - 1)][k - 1]);
        }
    }


    pre.resize(N + 1, 0); dp.resize(N + 1);
    FOR(i, 1, N) pre[i] = cost(1, i);
    for (int k = 2; k <= K; ++k){
        solve(1, N, 1, N);
        swap(pre, dp);
    }
    cout << pre[N];
}


signed main(){
    setupIO();
    int Test = 1;
//    cin >> Test;
    for ( int i = 1 ; i <= Test ; i++ ){
        Whisper();
        if (i < Test) cout << '\n';
    }
}

• Subtask 1: 0 / 14
• Subtask 2: 0 / 18
• Subtask 3: 0 / 21
• Subtask 4: 0 / 47