Submission #1142426

#	Time	Username	Problem	Language	Result	Execution time	Memory
1142426		g4yuhg	K blocks (IZhO14_blocks)	C++20	100 / 100	308 ms	81160 KiB

blocks

//Huyduocdithitp
#include <bits/stdc++.h>
typedef long long ll;
#define endl '\n'
#define yes cout<<"YES"<<endl;
#define no cout<<"NO"<<endl;
#define fi first
#define se second
#define pii pair<ll, ll>
#define inf 1e18
#define faster ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define MP make_pair
#define TASK "ghuy4g"
#define start if(fopen(TASK".inp","r")){freopen(TASK".inp","r",stdin);freopen(TASK".out","w",stdout);}
#define LOG 19
#define N 100005
using namespace std;
ll n, k;
ll a[N], f[N][101];
void sub2() {
    ll ln = 0;
    for (int i = 1; i <= n; i ++) {
        ln = max(ln, a[i]);
        f[i][1] = ln;
    }
    for (int j = 2; j <= k; j ++) {
        stack<pii> st;
        stack<ll> stmin;
        st.push({f[j - 1][j - 1], a[j]});
        stmin.push(st.top().fi + st.top().se);
        ll mini = st.top().fi + st.top().se;
        for (int i = j; i <= n; i ++) {
            f[i][j] = mini;
            mini = inf;
            pii moi = {f[i][j - 1], a[i + 1]};
            while (st.size() && st.top().se <= a[i + 1]) {
                moi.fi = min(moi.fi, st.top().fi);
                st.pop();
                stmin.pop();
            }
            if (st.size() && st.top().se > a[i + 1]) {
                mini = min(mini, st.top().fi + st.top().se);
            }
            if (stmin.size()) {
                stmin.push(min(moi.fi + moi.se, stmin.top()));
            }
            else {
                stmin.push(moi.fi + moi.se);
            }
            st.push(moi);
            mini = min(mini, moi.fi + moi.se);
            if (stmin.size()) mini = min(mini, stmin.top());
        }
    }
    cout << f[n][k];
}
void sub1() {
    memset(f, 60, sizeof(f));
    ll ln = 0;
    for (int i = 1; i <= n; i ++) {
        ln = max(ln, a[i]);
        f[i][1] = ln;
    }
    for (int j = 2; j <= k; j ++) {
        for (int i = j; i <= n; i ++) {
            ll maxi = a[i];
            for (int z = i; z >= j; z --) {
                maxi = max(maxi, a[z]);
                f[i][j] = min(f[i][j], maxi + f[z - 1][j - 1]);
                if (j == 2 && i == n && maxi + f[z - 1][j - 1] == 5) {
                    //cout << z - 1 << " " << j - 1 << " " << maxi << endl;
                }
            }
        }
    }
    cout << f[n][k];
}
signed main(void) {
    faster;
    cin >> n >> k;
    for (int i = 1; i <= n; i ++) {
        cin >> a[i];
    }
    sub2();
    return 0;
}

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