Submission #671303

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
671303	2022-12-12T19:09:27 Z	hct_2so1	K blocks (IZhO14_blocks)	C++17	Compilation error	0 ms	0 KB

blocks

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;
const int N = 1e5 + 5;
const ll INF = 1e18 + 7;
ll dp[N][3], n, k, a[N], st[4 * N];

void update(int id, int l, int r, int pos, ll val)
{
    if (l > r || pos < l || r < pos) return ;
    if (l == r)
    {
        st[id] = val;
        return ;
    }
    int mid = (l + r) / 2;
    if (pos <= mid) update(id * 2, l, mid, pos, val);
    else update(id * 2 + 1, mid + 1, r, pos, val);
    st[id] = min(st[id * 2], st[id * 2 + 1]);
}

int main()
{
    std::ios_base::sync_with_stdio(0); cin.tie(0);
    freopen("blocks.in", "r", stdin);
    freopen("blocks.out", "w", stdout);
    cin>>n>>k;
    for (int i = 1; i<=n; i++) cin>>a[i], dp[i][1] = max(dp[i - 1][1], a[i]);
    for (int i = 1; i<=4*n; i++) st[i] = INF;
    for (int j = 2; j<=k; j++)
    {
        stack<pair<int, ll>> s;
        int cur = k & 1;
        for (int i = j; i<=n; i++)
        {
            ll minF = dp[i - 1][1 - cur];
            while (s.size() && a[s.top().first] <= a[i])
                update(1, 1, n, s.top().first, INF), minF = min(minF, s.top().second), s.pop_back();
            dp[i][cur] = min(st[1], minF + a[i]);
            update(1, 1, n, i, dp[i][cur]);
            s.push_back({i, minF});
        }
    }
    //for (int i = 2; i<=n; i++) cout<<dp[i][k & 1]<<' ';
    cout<<dp[n][k & 1];
    return 0;
}

Compilation message

blocks.cpp: In function 'int main()':
blocks.cpp:39:90: error: 'class std::stack<std::pair<int, long long int> >' has no member named 'pop_back'
   39 |                 update(1, 1, n, s.top().first, INF), minF = min(minF, s.top().second), s.pop_back();
      |                                                                                          ^~~~~~~~
blocks.cpp:42:15: error: 'class std::stack<std::pair<int, long long int> >' has no member named 'push_back'
   42 |             s.push_back({i, minF});
      |               ^~~~~~~~~
blocks.cpp:26:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |     freopen("blocks.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:27:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |     freopen("blocks.out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~