Submission #203811

#	Time	Username	Problem	Language	Result	Execution time	Memory
203811		zufius	K개의 묶음 (IZhO14_blocks)	C++14	100 / 100	478 ms	81528 KiB

blocks

#include <iostream>
#include <stdio.h>
#include <deque>

using namespace std;

typedef long long ll;

const int N = 1e5 + 11;
const ll oo = 1e18;

int n,k,lastGreater[N];
ll f[N][101],a[N],minf[N],tmp[N];
deque <int> Q;

void init(){
    ll cur = -1;
    for(int i = 1; i <= n; ++i){
        cur = max(cur,a[i]);
        f[i][1] = cur;
    }
    for(int i = 1; i <= n; ++i){
        lastGreater[i] = 0;
        while(Q.size() && a[Q.back()] <= a[i]) Q.pop_back();
        if(Q.size()) lastGreater[i] = Q.back();
        Q.push_back(i);
    }

    //for(int i = 1; i <= n; ++i) cout << i << " ~> " << lastGreater[i] << endl;
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie();
    cout.tie();
    
    cin >> n >> k;
    for(int i = 1; i <= n; ++i) cin >> a[i];
    
    for(int i = 0; i <= n; ++i)
    for(int j = 1; j <= k; ++j) f[i][j] = oo;

    init();

    minf[0] = oo;
    //for(int i = 1; i <= n; ++i) cout << "lastGreater["<<i<<"] = " << lastGreater[i] << endl;

    /*for(int i = 1; i <= n; ++i){
        cout << "f["<<i<<"][1] = " << f[i][1] << endl;
    }*/

    for(int j = 2; j <= k; ++j){
        Q.clear();
        for(int i = 1; i <= n; ++i){
            minf[i] = f[i - 1][j - 1]; // minf[i] : from lastGreater[i] -> i - 1
            while(Q.size() && a[Q.back()] <= a[i]){
                minf[i] = min(minf[i],min(minf[Q.back()],f[Q.back()][j - 1]));
                Q.pop_back();
            }
            //cout << i << " => ["<< (Q.size() ? Q.back() : 0) << " -> " << i - 1<<"] = " << minf[i] << endl;
            Q.push_back(i);
        }
        for(int i = 1; i <= n; ++i) minf[i] += a[i];

        for(int i = 1; i <= n; ++i){
            f[i][j] = minf[i] = min(minf[i],minf[lastGreater[i]]);
        }
        /*cout << "j = " << j << " : " << endl;
        for(int i = 1; i <= n; ++i) cout << f[i][j] << " / ";
        cout << endl;
        for(int i = 1; i <= n; ++i) tmp[i] = f[i][j],f[i][j] = oo;
        for(int i = 1; i <= n; ++i){
            ll cc = 0;
            for(int v = i; v > 0; --v){
                cc = max(cc,a[v]);
                f[i][j] = min(f[i][j],f[v - 1][j - 1] + cc);
            }
            if(f[i][j] != tmp[i]){
                cout << "ok at f["<<i<<","<<j<<"] = " << f[i][j] << endl;
            }
        }
        for(int i = 1; i <= n; ++i) cout << f[i][j] << " / ";
        cout << endl << endl;*/
    }

    cout << f[n][k];

    return 0;
}

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