Submission #1125659

#	Time	Username	Problem	Language	Result	Execution time	Memory
1125659		CodeLakVN	K blocks (IZhO14_blocks)	C++17	100 / 100	168 ms	42228 KiB

blocks

#include <bits/stdc++.h>
using namespace std;

#define Task "main"
#define ll long long
#define pb push_back
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FOD(i, a, b) for (int i = (a); i >= (b); i--)
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
#define F first
#define S second

const int N = 1e5 + 5;
const int INF = 1e9;
const int MOD = 1e9 + 7;

template<class X, class Y>
    bool minimize(X &x, Y y) {
        if (x > y) {
            x = y;
            return true;
        } else return false;
    }

template<class X, class Y>
    bool maximize(X &x, Y y) {
        if (x < y) {
            x = y;
            return true;
        } else return false;
    }

int n, k;
int a[N];

namespace sub3 {
    const int N = 1e2 + 5;

    int dp[N][N];
    
    void solve() {
        memset(dp, 0x3f, sizeof(dp));
        dp[0][0] = 0;
        FOR(group, 1, k) FOR(i, group, n) {
            int maxx = a[i]; 
            FOD(j, i, 1) {
                maximize(maxx, a[j]);
                minimize(dp[group][i], dp[group - 1][j - 1] + maxx);
            }
        }

        cout << dp[k][n] << "\n";
    }
}

namespace subFull {
    int dp[105][N];

    void solve() {
        memset(dp, 0x3f, sizeof(dp));
        dp[0][0] = 0;
        a[0] = INF;
        FOR(group, 1, k) {
            stack<pair<int, int>> st;
            st.push({INF, INF});
            FOR(i, group, n) {
                int curDP = dp[group - 1][i - 1];
                while (!st.empty() && st.top().F <= a[i]) {
                    minimize(curDP, st.top().S);
                    st.pop();
                }
                if (st.top().F + st.top().S > a[i] + curDP) {
                    st.push({a[i], curDP});
                }
                dp[group][i] = st.top().F + st.top().S;
            }
        }

        cout << dp[k][n] << "\n";
    }
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    if (fopen(Task".INP", "r")) {
        freopen(Task".INP", "r", stdin);
        freopen(Task".OUT", "w", stdout);
    }
    
    cin >> n >> k;
    FOR(i, 1, n) cin >> a[i];

    if (n <= 100) sub3::solve();
    else subFull::solve();
    cerr << TIME << "s\n";

    return 0;
}

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:87:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |         freopen(Task".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
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(Task".OUT", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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