Submission #716787

#	Time	Username	Problem	Language	Result	Execution time	Memory
716787		pragmatist	Split the sequence (APIO14_sequence)	C++17	0 / 100	125 ms	6800 KiB

sequence

#include <bits/stdc++.h>                     
  
#define ll long long 
#define pb push_back
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
#define sz(v) (int)v.size()
#define x first
#define y second
#define nl "\n"
  
using namespace std;
  
const int N = (int)1e5 + 7;
const int M = (int)2e6 + 5e5 + 7;
const ll MOD = (ll)1e9;                    
const int inf = (int)1e9 + 7;
const int B = (int)390;
const ll INF = (ll)1e18 + 7;
  
pair<int, int> dir[] = {{-1, 0}, {1, 0}, {0, 1}, {0, -1}};
 
bool bit(int mask, int i) {
    return (mask >> i & 1);
}
  
int sum(int x, int y) {
    x += y;
    if(x >= MOD) x -= MOD;
    return x;
}
  
int mult(int x, int y) {
    return 1ll * x * y % MOD;
}

int n, k, a[N], suf[N], p[1001][201];
ll dp[1001][201];

void solve() {
	cin >> n >> k;
	for(int i = 1; i <= n; ++i) cin >> a[i];
	for(int i = n; i >= 1; --i) suf[i] = suf[i + 1] + a[i];
	ll ans = -INF;
	int lst = -1;

	for(int i = 1; i < n; ++i) {
		for(int l = 1; l <= k; ++l) {
			dp[i][l] = -INF;
			for(int j = i; j >= 1; --j) {
		    	if(dp[j - 1][l - 1] + (suf[j] - suf[i + 1]) * suf[i + 1] > dp[i][l]) {
		    		dp[i][l] = dp[j - 1][l - 1] + (suf[j] - suf[i + 1]) * suf[i + 1];
		    		p[i][l] = j;
		    	}
			}
		}
		if(dp[i][k] > ans) {
			ans = dp[i][k];
			lst = i;
		}
	}
	assert(lst != -1);
	vector<int> v;
	while(lst > 0) {
		v.pb(lst);
		lst = p[lst][k--] - 1;
	} 
	reverse(all(v));
	cout << ans << nl;
	for(auto x : v) cout << x << ' ';
	
}       
 
  
signed main() {                   
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    //freopen("sequence.in", "r", stdin);
    //freopen("sequence.out", "w", stdout);     
    int test = 1;                       
    //cin >> test;
    for(int i = 1; i <= test; ++i) {
        //cout << "Case " << i << ":\n";
        solve();
    }
    return 0;
}                   
/*
possible causes of error :
* array  bounds
* int overflow
* special case (n == 1?)
* haven't clean something
* wrong N | M | inf | INF | MOD

* try to write brute force to find test
* don't waste time
* don't write bullshit
* solution is easy
*/

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