Submission #989910

#	Time	Username	Problem	Language	Result	Execution time	Memory
989910		awf	Split the sequence (APIO14_sequence)	C++14	49 / 100	62 ms	131072 KiB

sequence

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

const int N = 1e5 + 15;
#define int long long

int a[N];
int b[N];
int n, k;
int dp[N][215];
int pre[N];
int nm; 
int w[N];
int x[N];
int tv[N][215];
int id = 0;

int cost(int l, int r){
	return (pre[r] - pre[l-1]) * (pre[n] - pre[r]);
}

void cal(int k, int l, int r, int opl, int opr) {
    if (l > r) return;
    int mid = (l + r) / 2;
    int opm = -1;
    dp[mid][k] = 0;
    for (int i = opr; i >= opl; i--) {
        int val = dp[i][k-1] + cost(i+1,mid);
        if (val > dp[mid][k]) {
            dp[mid][k] = val;
            opm = i;
        }
    }
    tv[mid][id] = opm;
    // cout << mid << " " << id << " " << opm << endl;
    cal(k, l, mid - 1, opl, opm);
    cal(k, mid + 1, r, opm, opr);
}
signed main() {
    ios_base::sync_with_stdio();
    cin.tie(0);
    cin >> n >> k;
    for (int i = 1; i <= n; i++) cin >> a[i];
    
    for (int i = 1; i <= n; i++) {
        pre[i] = pre[i-1] + a[i];
    }
	
    for (int i = 1; i <= n; i++) dp[i][1] = cost(1,i);

    for (int i = 2; i <= k; i++) {
    	id++;
        cal(i, 1, n, 1, n);
        // for (int j = 1; j <= n; j++) {
            // dp[j][0] = dp[j][1];
            // dp[j][1] = 0;
        // }
    }
    // for(int i=2; i<=k; i++){
    	// for(int j=1; j<=n; j++){
    		// cout << dp[j][i] << endl;
    	// }
    	// cout << endl;
    // }
	int mx = 0;
	int last = 0;
	for(int i=1; i<=n; i++){
		if(mx < dp[i][k]){
			last = i;
			mx = dp[i][k];
		}
	}
	cout << mx << endl;
	for(int i=k-1; i>=0; i--){
		cout << last << " ";
		// cout << last << " " << i << " " << tv[last][i] << endl;
		last = tv[last][i]; 
	}
}

• Subtask 1: 0 / 11
• Subtask 2: 11 / 11
• Subtask 3: 0 / 11
• Subtask 4: 17 / 17
• Subtask 5: 21 / 21
• Subtask 6: 0 / 29