Submission #800465

#	Time	Username	Problem	Language	Result	Execution time	Memory
800465		GrindMachine	Feast (NOI19_feast)	C++17	53 / 100	1059 ms	10912 KiB

feast

// Om Namah Shivaya

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a, b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a, b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
edi

*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

void solve(int test_case)
{
    ll n,k; cin >> n >> k;
    vector<ll> a(n+5);
    rep1(i,n) cin >> a[i];

    vector<ll> b;
    b.pb(a[1]);
    
    for(int i = 2; i <= n; ++i){
        bool diff = false;
        if(a[i] < 0 and b.back() > 0) diff = true;
        if(a[i] > 0 and b.back() < 0) diff = true;
        if(diff){
            b.pb(a[i]);
        }
        else{
            b.back() += a[i];
        }
    } 

    if(b.front() <= 0){
        b.erase(b.begin());
    }
    if(sz(b) and b.back() <= 0){
        b.pop_back();
    }

    ll ans = 0;

    while(true){
        vector<ll> positives;
        rep(i,sz(b)){
            if(b[i] > 0){
                positives.pb(b[i]);
            }
        }

        sort(rall(positives));

        ll val = 0;
        rep(i,min((ll)sz(positives),k)){
            val += positives[i];
        }

        amax(ans,val);

        if(sz(positives) <= k) break;
        
        ll mn_abs = inf2, pos = -1;
        rep(i,sz(b)){
            if(abs(b[i]) < mn_abs){
                mn_abs = abs(b[i]);
                pos = i;
            }
        }

        b.insert(b.begin(),0);
        b.pb(0);

        pos++;

        b[pos] += b[pos-1];
        b[pos] += b[pos+1];
        b[pos-1] = b[pos+1] = 0;

        vector<ll> c;
        c.pb(b[0]);

        rep1(i,(ll)sz(b)-1){
            bool diff = false;
            if(b[i] < 0 and c.back() > 0) diff = true;
            if(b[i] > 0 and c.back() < 0) diff = true;
            if(diff){
                c.pb(b[i]);
            }
            else{
                c.back() += b[i];
            }
        }

        if(c.front() <= 0){
            c.erase(c.begin());
        }
        if(sz(c) and c.back() <= 0){
            c.pop_back();
        }

        b = c;
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;

    rep1(i, t) {
        solve(i);
    }

    return 0;
}

Compilation message (stderr)

feast.cpp: In function 'void solve(int)':
feast.cpp:30:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 | #define rep(i, n) for(int i = 0; i < n; ++i)
      |                                    ^
feast.cpp:95:9: note: in expansion of macro 'rep'
   95 |         rep(i,sz(b)){
      |         ^~~
feast.cpp:110:26: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
  110 |         if(sz(positives) <= k) break;
      |                          ^
feast.cpp:30:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 | #define rep(i, n) for(int i = 0; i < n; ++i)
      |                                    ^
feast.cpp:113:9: note: in expansion of macro 'rep'
  113 |         rep(i,sz(b)){
      |         ^~~

• Subtask 1: 4 / 4
• Subtask 2: 8 / 8
• Subtask 3: 0 / 18
• Subtask 4: 10 / 10
• Subtask 5: 11 / 11
• Subtask 6: 20 / 20
• Subtask 7: 0 / 29