Submission #670092

#	Time	Username	Problem	Language	Result	Execution time	Memory
670092		radal	Split the sequence (APIO14_sequence)	C++17	100 / 100	945 ms	84252 KiB

sequence

#include <bits/stdc++.h>
#pragma GCC target("sse,sse2,avx2")
#pragma GCC optimize("unroll-loops,O2")
#define rep(i,l,r) for (int i = l; i < r; i++)
#define repr(i,r,l) for (int i = r; i >= l; i--)
#define X first
#define Y second
#define all(x) (x).begin() , (x).end()
#define pb push_back
#define endl '\n'
#define debug(x) cerr << #x << " : " << x << endl;
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pll;
constexpr int N = 1e5+10,mod = 1e9+7,maxm = 210;
constexpr ll inf = 1e18+10;
inline int mkay(int a,int b){
    if (a+b >= mod) return a+b-mod;
   // if (a+b < 0) return a+b+mod;
    return a+b;
}

inline int poww(int a,int k){
    if (k < 0) return 0;
    int z = 1;
    while (k){
        if (k&1) z = 1ll*z*a%mod;
        a = 1ll*a*a%mod;
        k >>= 1;
    } 
    return z; 
}

ll dp[2][N],ps[N];
int opt[maxm][N],a[N];
vector<int> ve;
vector<pll> baz;

ll bar(int i,int j,int k){
	return (dp[k][i]-ps[i]*ps[i]-dp[k][j]+ps[j]*ps[j]+ps[j]-ps[i]-1)/(ps[j]-ps[i]);
}

int main(){
	ios :: sync_with_stdio(0);	cin.tie(0);
	int n,k;
	cin >> n >> k;
	rep(i,1,n+1){
	   	cin >> a[i];
		ps[i] = ps[i-1]+a[i];
		dp[1][i] = 0;
	}
	k++;
	rep(i,2,k+1){
		bool d = i&1;
		ve.clear();
		baz.clear();
		ve.pb(0);
		baz.pb({0,inf});
		rep(j,1,n+1){
			int ind = lower_bound(all(baz),make_pair(ps[j]+1,0ll))-1-baz.begin();
			int x = ve[ind];
			opt[i][j] = x;
			dp[d][j] = dp[1-d][x]+ps[x]*(ps[j]-ps[x]);
			while (!ve.empty()){
				x = ve.back();
				if (ps[x] == ps[j]){
					if (dp[1-d][x]-ps[x]*ps[x] <= dp[1-d][j]-ps[j]*ps[j]){
						baz.pop_back();
						ve.pop_back();
						continue;
					}
					break;
				}
				ll tmp = bar(x,j,1-d);
				if (tmp <= baz.back().X){
					baz.pop_back();
					ve.pop_back();
					continue;
				}
				break;
			}
			if (ve.empty()){
				ve.pb(j);
				baz.pb({0,inf});
				continue;
			}
			x = ve.back();
			if (ps[x] == ps[j]) continue;
			ll tmp = bar(x,j,1-d);
			baz.back().Y = tmp;
			ve.pb(j);
			baz.pb({baz.back().Y,inf});
		}
	}
	cout << dp[k&1][n] << endl;
	vector<int> ans;
	int cur = n,cnt = k;
	while(cnt > 1){
		ans.pb(opt[cnt][cur]);
		cur = opt[cnt][cur];
		cnt--;
	}
	sort(all(ans));
	for (int u : ans) cout << u << ' ';
	cout << endl;
}

• Subtask 1: 11 / 11
• Subtask 2: 11 / 11
• Subtask 3: 11 / 11
• Subtask 4: 17 / 17
• Subtask 5: 21 / 21
• Subtask 6: 29 / 29