Submission #893916

#	Time	Username	Problem	Language	Result	Execution time	Memory
893916		kigash	Split the sequence (APIO14_sequence)	C++17	50 / 100	105 ms	13344 KiB

sequence

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

// #pragma comment(linker, "/stack:200000000")
// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")

using ll = long long;
using ld = long double;
#define pb push_back
#define ff first
#define ss second
#define sz(x) (ll)(x).size()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()

void freopen(string s) { freopen((s+".in").c_str(), "r", stdin); freopen((s+".out").c_str(), "w", stdout); }
void IOIGold2024_InshAllah() { ios_base::sync_with_stdio(false); cin.tie(NULL); }
ll binmul(ll a, ll b, ll c) { ll res = 0; while(b) { if(b&1) (res += a) %= c; (a += a) %= c; b >>= 1; } return res; }
ll binpow(ll a, ll b, ll c) { ll res = 1; while(b) { if(b&1) (res *= a) %= c; (a *= a) %= c; b >>= 1; } return res; }
template<typename T> T gcd(T a, T b) { if(b==0) return a; return gcd(b, a%b); }
template<typename T> T lcm(T a, T b) { return a/gcd(a, b)*b; }
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ld rnd() { return rng()%INT_MAX*1.0/INT_MAX; }

const ll inf = 1e18+7, MX = LLONG_MAX, MN = LLONG_MIN;
const ll mod = 1e9+7, N = 3e5+5;
ll a[N], pr[N], dp[1005][205];

void kigash() {
    ll n, k, x = 1, mx = 0;
    cin>>n>>k;
    for(ll i=1; i<=n; i++) cin>>a[i], pr[i] = pr[i-1]+a[i];
    for(ll i=1; i<=n; i++) {
        for(ll j=1; j<=min(i, k); j++) {
            for(ll l=j-1; l<i-(i==n); l++) {
                dp[i][j] = max(dp[i][j], dp[l][j-1]+(pr[i]-pr[l])*(pr[n]-pr[i]));
            }
        }
        if(i>=k && dp[i][k]>mx) mx = dp[i][k], x = i;
    }
    vector<ll> ans;
    cout<<mx<<"\n";
    ans.pb(x);
    while(k--) {
        ll pos = -1;
        for(ll i=k; i<x-(x==n); i++) {
            if(dp[x][k+1]==dp[i][k]+(pr[x]-pr[i])*(pr[n]-pr[x])) {
                pos = i;
                break;
            }
        }
        x = pos;
        if(k) ans.pb(x);
    }
    reverse(all(ans));
    for(auto x: ans) cout<<x<<" ";
    return;
}

signed main(/*Kigash Amir*/) {
    // freopen("");
    IOIGold2024_InshAllah();
    ll tt = 1;
    // cin>>tt;
    for(ll i=1; i<=tt; i++) {
        kigash();
    }
}

Compilation message (stderr)

sequence.cpp: In function 'void freopen(std::string)':
sequence.cpp:17:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | void freopen(string s) { freopen((s+".in").c_str(), "r", stdin); freopen((s+".out").c_str(), "w", stdout); }
      |                          ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sequence.cpp:17:73: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 | void freopen(string s) { freopen((s+".in").c_str(), "r", stdin); freopen((s+".out").c_str(), "w", stdout); }
      |                                                                  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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