Submission #258288

#	Time	Username	Problem	Language	Result	Execution time	Memory
258288		karma	K blocks (IZhO14_blocks)	C++14	100 / 100	178 ms	3068 KiB

blocks

#include <bits/stdc++.h>
#define pb          emplace_back
#define ll          long long
#define fi          first
#define se          second
#define mp          make_pair
//#define int         int64_t

using namespace std;

const int N = int(1e6) + 7;
const int inf = 1e9 + 1;
typedef pair<ll, ll> pii;

struct TNode {
    int x, y, ans;
    TNode() {x = y = ans = inf;}
    TNode(int x, int y): x(x), y(y) {
        ans = x + y;
    }
    void minimize(const TNode& o) {
        x = min(x, o.x);
        ans = min(ans, x + y);
    }
} cur;
int f[2][N], n, k, a[N];
vector<TNode> v;

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    #define Task        "test"
    if(fopen(Task".inp", "r")) {
        freopen(Task".inp", "r", stdin);
        freopen(Task".out", "w", stdout);
    }
    cin >> n >> k;
    for(int i = 1; i <= n; ++i) {
        cin >> a[i];
        f[1][i] = max(f[1][i - 1], a[i]);
    }
    for(int i = 2; i <= k; ++i) {
        v.clear();
        for(int j = i; j <= n; ++j) {
            cur = TNode(f[(i & 1) ^ 1][j - 1], a[j]);
            while(v.size() && v.back().y <= cur.y) {
                cur.minimize(v.back());
                v.pop_back();
            }
            if(v.size()) cur.ans = min(cur.ans, v.back().ans);
            f[i & 1][j] = cur.ans;
            v.pb(cur);
        }
    }
    cout << f[k & 1][n];
}

Compilation message (stderr)

blocks.cpp: In function 'int32_t main()':
blocks.cpp:34:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".inp", "r", stdin);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:35:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
         freopen(Task".out", "w", stdout);
         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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