Submission #534398

#	Time	Username	Problem	Language	Result	Execution time	Memory
534398		idas	Feast (NOI19_feast)	C++11	12 / 100	101 ms	9700 KiB

feast

#include <bits/stdc++.h>
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr)
#define f first
#define s second
#define pb push_back
#define sz(x) ((int)((x).size()))
#define le(vec) vec[vec.size()-1]
#define all(x) (x).begin(), (x).end()
#define TSTS int ttt; cin >> ttt; while(ttt--) solve()

using namespace std;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long double, long double> pdd;
typedef map<int, int> mii;
typedef vector<int> vi;
typedef long double ld;
typedef long long ll;

const int INF=1e9, MOD=1e9+7, mod=998244353;
const ll LINF=1e18;

void setIO()
{
    FAST_IO;
}

void setIO(string s)
{
    FAST_IO;
    freopen((s+".in").c_str(), "r", stdin);
    freopen((s+".out").c_str(), "w", stdout);
}

const int N=3e5+10;
int n, k;
ll a[N], p[N];
pair<ll, int> dp[N];

bool can(ll x)
{
    FOR(i, 0, n+1) dp[i]={0,0};
    pair<ll, int> best={0,0};
    FOR(i, 1, n+1)
    {
        dp[i]=max(dp[i-1], {best.f-x+p[i],best.s-1});
        best=max(best, {dp[i].f-p[i],dp[i].s});
    }
    return -dp[n].s<=k;
}

ll build(ll x)
{
    FOR(i, 0, n+1) dp[i]={0,0};
    pair<ll, int> best={0,0};
    FOR(i, 1, n+1)
    {
        dp[i]=max(dp[i-1], {best.f-x+p[i],best.s-1});
        best=max(best, {dp[i].f-p[i],dp[i].s});
    }
    return dp[n].f-dp[n].s*x;
}

int  main()
{
    setIO();
    cin >> n >> k;
    FOR(i, 1, n+1) cin >> a[i];
    FOR(i, 1, n+1) p[i]=p[i-1]+a[i];

    int l=0, r=INF;
    while(l<r){
        int m=(l+r)/2;
        if(can(m)) r=m;
        else l=m+1;
    }

    cout << build(l);
}

Compilation message (stderr)

feast.cpp: In function 'void setIO(std::string)':
feast.cpp:32:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     freopen((s+".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
feast.cpp:33:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |     freopen((s+".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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