Submission #1198679

#	Time	Username	Problem	Language	Result	Execution time	Memory
1198679		4o2a	K blocks (IZhO14_blocks)	C++20	0 / 100	0 ms	328 KiB

blocks

#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
#define _F "test"
using namespace std;
typedef long long ll;

constexpr ll INF = 1e18;
ll st[400001];

void upd(int v, int tl, int tr, int pos, ll val)
{
    if (tl == tr)
        st[v] = val;
    else
    {
        int tm = (tl+tr)/2;
        if (pos <= tm)
            upd(2*v, tl, tm, pos, val);
        else
            upd(2*v+1, tm+1, tr, pos, val);
        st[v] = min(st[2*v], st[2*v+1]);
    }
}

ll getmin(int v, int tl, int tr, int l, int r)
{
    if (l > r)
        return INF;
    if (l <= tl && tr <= r)
        return st[v];
    int tm = (tl+tr)/2;
    return min(getmin(2*v, tl, tm, l, min(r, tm)),
               getmin(2*v+1, tm+1, tr, max(l, tm+1), r));
}

void solve()
{
    int n, k, cur = 0, app = 1; cin>>n>>k;
    vector<int> val(n+1), pre(n+1); val[0] = 10000000;
    vector<vector<int>> idx(1001);
    stack<int> temp; temp.push(0);
    vector<vector<ll>> dp(k+1, vector<ll>(n+1, INF));
    for (int i = 1; i <= n; ++i)
    {
        cin>>val[i];
        idx[val[i]].pb(i);
        if (val[i] > cur)
        {
            cur = val[i];
            app = 1;
        }
        else if (val[i] == cur)
            ++app;
        dp[1][i] = app*cur;
        while (val[i] >= val[temp.top()])
            temp.pop();
        pre[i] = temp.top();
        temp.push(i);
    }
    for (int i = 2; i <= k; ++i)
    {
        for (int j = 1; j <= n; ++j)
            upd(1, 1, n, j, val[j] + dp[i-2][j-1]);
        for (int j = i; j <= n; ++j)
        {
            dp[i][j] = min(dp[i][pre[j]], dp[i-1][j-1] + val[j]);
            if (pre[j]+1 < j)
            {
                auto x1 = lower_bound(idx[val[j]].begin(), idx[val[j]].end(), j);
                auto x2 = lower_bound(idx[val[j]].begin(), idx[val[j]].end(), pre[j]+1);
                int cnt = x1 - x2 + 1;
                if (cnt > 1)
                    dp[i][j] = min(dp[i][j], dp[i][j-1] + val[j]);
                int pos = max((x1 == idx[val[j]].begin() ? 0 : *prev(x1)), pre[j]);
                dp[i][j] = min(dp[i][j], getmin(1, 1, n, pos+1, j-1) + val[j]);
            }
        }
    }
    cout<<dp[k][n];
}

int main()
{
    if (fopen(_F".INP", "r"))
    {
        freopen(_F".INP", "r", stdin);
        //freopen(_F".OUT", "w", stdout);
    }
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int Test = 1; //cin>>Test;
    while (Test--) solve();
}

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:88:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |         freopen(_F".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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