Submission #57413

#	Time	Username	Problem	Language	Result	Execution time	Memory
57413		Benq	K blocks (IZhO14_blocks)	C++14	100 / 100	352 ms	50968 KiB

blocks

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;

int N,K, dp[101][MX],A[MX];
vpi bes;

void ins(int x, int y) {
    if (x == 0 && y > 0) return;
    while (sz(bes) && bes.back().f >= dp[x][y]) bes.pop_back();
    bes.pb({dp[x][y],-MOD});
}

void process(int x) {
    int mn = MOD;
    while (sz(bes) && bes.back().s <= x) {
        mn = bes.back().f;
        bes.pop_back();
    }
    if (!sz(bes) || bes.back().f+bes.back().s > mn+x) bes.pb({mn,x});
} 

void solve(int x) {
    bes.clear();
    FOR(i,x,N+1) {
        ins(x-1,i-1);
        process(A[i]);
        dp[x][i] = bes.back().f+bes.back().s;
    }
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N >> K;
    FOR(i,1,N+1) cin >> A[i];
    FOR(i,1,K+1) solve(i);
    cout << dp[K][N];
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
*/

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