Submission #553661

#	Time	Username	Problem	Language	Result	Execution time	Memory
553661		kwongweng	Split the sequence (APIO14_sequence)	C++17	39 / 100	2093 ms	31956 KiB

sequence

#include <bits/stdc++.h>
using namespace std;
 
#pragma GCC target ("avx2")
#pragma GCC optimization ("Ofast")
#pragma GCC optimization ("unroll-loops")
 
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef long double ld;
typedef pair<ll, ll> pll;
#define FOR(i, a, b) for(int i = a; i < b; i++)
#define ROF(i, a, b) for(int i = a; i >= b; i--)
#define ms memset
#define pb push_back
#define fi first
#define se second
 
ll MOD = 1000000007;
 
ll power(ll base, ll n){
	if (n == 0) return 1;
	if (n == 1) return base;
	ll halfn = power(base, n/2);
	if (n % 2 == 0) return (halfn * halfn) % MOD;
	return (((halfn * halfn) % MOD) * base) % MOD;
}
 
ll inverse(ll n){
	return power(n, MOD-2);
}
 
ll add(ll a, ll b){
	return (a+b) % MOD;
}
 
ll mul(ll a, ll b){
	a %= MOD;
	return (a*b) % MOD;
}
 
ll gcd(ll a, ll b){
    if (a == 1) return 1;
    if (a == 0) return b;
    return gcd(b%a, a);
}
 
const int N = 10001;

void solve(){
    // brute force O(n^2 * k)
    int n, k; cin >> n >> k;
    vector<ll> a(n+1); FOR(i,1,n+1) cin >> a[i];
    vector<ll> s(n+1); FOR(i,1,n+1) s[i]=a[i]+s[i-1];
    ll dp[n+1][k+1], pos[n+1][k+1];
    ms(dp,0,sizeof(dp));
    ms(pos,-1,sizeof(pos));
    FOR(i,1,n+1){
        dp[i][0] = s[i] * (s[n]-s[i]);
        FOR(j,1,min(i,k+1)){
            FOR(l,1,i){
                ll val = dp[l][j-1] + (s[i]-s[l])*(s[n]-s[i]+s[l]);
                if (val > dp[i][j] && dp[l][j-1] != 0){
                    dp[i][j]=val;
                    //cout<<i<<" "<<j<<" "<<val<<" "<<val-dp[l][j-1]<<'\n';
                    pos[i][j]=l;
                }
            }
        }
    }
    cout << dp[n][k]/2 << '\n';
    int cur = n;
    vi b;
    ROF(i,k,1){
        cur = pos[cur][i];
        b.pb(cur);
    }
    ROF(i,k-1,0){
        cout << b[i]<<" ";
    }
    cout << '\n';
    return;
}
 
int main() {
    ios::sync_with_stdio(false);
    int TC = 1;
    //cin >> TC;
    FOR(i, 1, TC+1){
        //cout << "Case #" << i << ": ";
        solve();
    }
}

Compilation message (stderr)

sequence.cpp:5: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    5 | #pragma GCC optimization ("Ofast")
      | 
sequence.cpp:6: warning: ignoring '#pragma GCC optimization' [-Wunknown-pragmas]
    6 | #pragma GCC optimization ("unroll-loops")
      |

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