Submission #1261374

#	Time	Username	Problem	Language	Result	Execution time	Memory
1261374		blueviolet	K blocks (IZhO14_blocks)	C++20	32 / 100	1 ms	1864 KiB

blocks

#include             <bits/stdc++.h>
    
#define             ll   long long
#define          io(x)   if (fopen(x".inp","r")) {freopen(x".inp","r",stdin),freopen(x".out","w",stdout);}
#define        TimeRun   {End=clock();cerr<<"Time run: "<<(float)(End-Begin)/CLOCKS_PER_SEC<<"s"<<el;}
#define      mem(c, x)   memset(c, x, sizeof(c))
#define         all(c)   c.begin(), c.end()
#define       bit(i,j)   ((i >> j) & 1)
#define             se   second     
#define             fi   first
#define             el   '\n'
using namespace std;  

template<class X, class Y> bool maximize(X &a, const Y &b) { return (a < b ? a = b, 1 : 0); }
template<class X, class Y> bool minimize(X &a, const Y &b) { return (a > b ? a = b, 1 : 0); }

int dx[8] = {0, 1, 0,-1, 1, 1,-1,-1};
int dy[8] = {1, 0,-1, 0, 1,-1,-1, 1};
const int  maxn  = 2e4 + 2;
const int  Inf   = 2e9 + 7;
const ll   Infll = 1e18 + 9;
const ll   Mod   = 1e9 + 7;
/*~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/
int L[maxn], R[maxn], n, k, a[maxn];

struct SegmentTree
{
    ll lz[maxn << 2], st[maxn << 2];
    void down(int id, int l, int r) {
        minimize(lz[id << 1], lz[id]);
        minimize(lz[id << 1|1], lz[id]);
        minimize(st[id << 1], lz[id]);
        minimize(st[id << 1|1], lz[id]);
        lz[id] = Infll;
    }

    void build(int id, int l, int r) {
        lz[id] = Infll;
        if (l == r) {
            st[id] = Infll;
            return;
        }

        int mid = l + r >> 1; 
        build(id << 1, l, mid);
        build(id << 1|1, mid + 1, r);

        st[id] = min(st[id << 1], st[id << 1|1]);
    }
    void update(int id, int l, int r, int u, int v, ll val) {
        if (l > v || r < u) return;
        if (u <= l && r <= v) {
            minimize(st[id], val);
            minimize(lz[id], val);
            return;
        }

        int mid = l + r >> 1; 
        down(id, l, r);
        update(id << 1, l, mid, u, v, val);
        update(id << 1|1, mid + 1, r, u, v, val);

        st[id] = min(st[id << 1], st[id << 1|1]);
    }

    ll get(int id, int l, int r, int u, int v) {
        if (l > v || r < u) return Infll; 
        if (l >= u && r <= v) return st[id];

        int mid = l + r >> 1; 
        down(id, l, r);
        ll get1 = get(id << 1, l, mid, u, v);
        ll get2 = get(id << 1|1, mid + 1, r, u, v);

        return min(get1, get2); 
    }
} seg[100];
void buildLR() {
    stack<int> st;
    for (int i=1; i<=n; i++) {
        while (st.size() && a[st.top()] <= a[i]) st.pop();
        L[i] = (int)st.size() == 0 ? 1 : st.top() + 1;
        st.push(i);
    }
    while (st.size()) st.pop();
    for (int i=n; i>=1; i--) {
        while (st.size() && a[st.top()] <= a[i]) st.pop();
        R[i] = (int)st.size() == 0 ? n : st.top() - 1;
        st.push(i);
    }
}
void solve() {
    cin >> n >> k;
    for (int i=1; i<=n; i++) cin >> a[i];
    buildLR();

    for (int i=0; i<=k; i++) seg[i].build(1, 0, n);
    seg[0].update(1, 0, n, 0, 0, 0);

    for (int i=1; i<=n; i++) {
        for (int j=1; j<=min(i, k); j++) {
            ll minDp = seg[j-1].get(1, 0, n, L[i]-1, i-1) + a[i];
            seg[j].update(1, 0, n, i, R[i], minDp);
        }
    }
    cout << seg[k].get(1, 0, n, n, n);
}

signed main() {
    
    ios_base::sync_with_stdio(false);  cin.tie(0); cout.tie(0); clock_t Begin = clock(), End;
    io("task"); 

    solve();
    
    TimeRun; return (0 ^ 0);
}

Compilation message (stderr)

blocks.cpp: In function 'int main()':
blocks.cpp:4:58: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    4 | #define          io(x)   if (fopen(x".inp","r")) {freopen(x".inp","r",stdin),freopen(x".out","w",stdout);}
      |                                                   ~~~~~~~^~~~~~~~~~~~~~~~~~~
blocks.cpp:112:5: note: in expansion of macro 'io'
  112 |     io("task");
      |     ^~
blocks.cpp:4:85: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    4 | #define          io(x)   if (fopen(x".inp","r")) {freopen(x".inp","r",stdin),freopen(x".out","w",stdout);}
      |                                                                              ~~~~~~~^~~~~~~~~~~~~~~~~~~~
blocks.cpp:112:5: note: in expansion of macro 'io'
  112 |     io("task");
      |     ^~

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