Submission #697615

#	Time	Username	Problem	Language	Result	Execution time	Memory
697615		tamthegod	Split the sequence (APIO14_sequence)	C++17	50 / 100	153 ms	3796 KiB

sequence

// Make the best become better
// No room for laziness
#include<bits/stdc++.h>

#define int long long
#define pb push_back
#define fi first
#define se second
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 1e3 + 5;
const int maxK = 205;
const int mod = 1e9 + 7;
const ll oo = 1e18;
int n, k, a[maxN], sum[maxN];
int f[maxN][maxK];
void ReadInput()
{
    cin >> n >> k;
    for(int i=1; i<=n; i++)
    {
        cin >> a[i];
        sum[i] = sum[i - 1] + a[i];
    }
}
int get(int l, int r)
{
    if(l > r) return 0;
    return sum[r] - sum[l - 1];
}
void Solve()
{
   //cout << get(1, n);return
    memset(f, -3, sizeof f);
    f[0][0] = 0;
    for(int i=1; i<n; i++)
    {
        for(int j=1; j<=k; j++)
        {
            for(int t=i; t>=1; t--)
            {
                f[i][j] = max(f[i][j], f[t - 1][j - 1] + get(t, i) * get(i + 1, n));
            }
        }
    }
    int res = -1;
    int id = 0;
    for(int i=k; i<n; i++)
    {
        if(res < f[i][k])
        {
            res = f[i][k];
            id = i;
        }
    }
    cout << res << '\n';
    int tmp = res;
    vector<int> trace;
    trace.pb(id);
    for(int i=id-1; i>=1; i--)
    {
        if(f[i][k - 1] + get(i + 1, id) * get(id + 1, n) == res)
        {
            trace.pb(i);
            id = i;
            res = f[i][k - 1];
            k--;
        }
    }
    reverse(trace.begin(), trace.end());
    for(int v : trace) cout << v << " ";
    int sum = 0;
    int last = 0;
    for(int v : trace)
    {
        sum += get(last + 1, v) * get(v + 1, n);
        last = v;
    }
    assert(sum == tmp);
}
int32_t main()
{
   // freopen("sol.inp", "r", stdin);
   // freopen("sol.out", "w", stdout);
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    ReadInput();
    Solve();
}

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