Submission #679408

#	Time	Username	Problem	Language	Result	Execution time	Memory
679408		bachhoangxuan	Feast (NOI19_feast)	C++17	100 / 100	136 ms	10408 KiB

feast

// Judges with GCC >= 12 only needs Ofast
// #pragma GCC optimize("O3,no-stack-protector,fast-math,unroll-loops,tree-vectorize")
// MLE optimization
// #pragma GCC optimize("conserve-stack")
// Old judges
// #pragma GCC target("sse4.2,popcnt,lzcnt,abm,mmx,fma,bmi,bmi2")
// New judges. Test with assert(__builtin_cpu_supports("avx2"));
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma,tune=native")
// Atcoder
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma")
#include<bits/stdc++.h>
using namespace std;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
uniform_real_distribution<> pp(0.0,1.0);
#define int long long
#define pii pair<int,int>
const int inf=1e18;
const int mod=998244353;
const int maxn=300005;
const int maxl=20;
const int maxa=1000005;
int power(int a,int n){
    int res=1;
    while(n){
        if(n&1) res=res*a%mod;
        a=a*a%mod;n>>=1;
    }
    return res;
}
int n,k,a[maxn],ans;
pii dp[maxn];
pii check(int mid){
    pii Max={0,0};
    dp[0]={0,0};
    for(int i=1;i<=n;i++){
        dp[i]=max(make_pair(Max.first+a[i]-mid,Max.second+1),dp[i-1]);
        Max=max(Max,make_pair(dp[i].first-a[i],dp[i].second));
    }
    //cout << mid << ' ' << dp[n].first << ' ' << dp[n].second << '\n';
    return dp[n];
}
void solve(){
    cin >> n >> k;
    for(int i=1;i<=n;i++){cin >> a[i];a[i]+=a[i-1];}
    int l=0,r=3e14;
    while(r>=l){
        int mid=(r+l)>>1;
        pii p=check(mid);
        if(p.second<=k){ans=p.first+mid*p.second;r=mid-1;}
        else l=mid+1;
    }
    cout << ans << '\n';
}
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);cout.tie(NULL);
    int t=1;//cin >> t;
    while(t--) solve();
}

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