Submission #1007984

#	Time	Username	Problem	Language	Result	Execution time	Memory
1007984		Luvidi	Feast (NOI19_feast)	C++17	12 / 100	40 ms	12748 KiB

feast

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

#define ll long long
#define pll pair<ll, ll>
#define pii pair<int, int>
#define fs first
#define sc second
#define pb push_back

void solve() {
    int n,k;
    cin>>n>>k;
    ll a[n];
    for(int i=0;i<n;i++)cin>>a[i];
    vector<pair<pll,pll>> v;
    ll sum=0,s=a[0]>=0,l=0,cnt=0,ans=0;
    for(int i=0;i<n;i++){
        if(s^(a[i]>=0)){
            v.pb({{abs(sum),s},{l,i-1}});
            if(s){
                cnt++;
                ans+=sum;
            }
            s=!s;
            sum=0;
            l=i;
        }
        sum+=a[i];
    }
    v.pb({{abs(sum),s},{l,n-1}});
    if(s){
        cnt++;
        ans+=sum;
    }
    bool b[n];
    for(int i=0;i<n;i++)b[i]=a[i]>=0;
    sort(v.begin(),v.end());
    int idx=0;
    while(cnt>k){
        if(idx==v.size())break;
        auto[x,y]=v[idx].fs;
        auto[l,r]=v[idx].sc;
        idx++;
        if(y){
            if(l>0&&b[l-1]||r<n-1&&b[r+1])continue;
            for(int i=l;i<=r;i++)b[i]=0;
            ans-=x;
        }else{
            if(!l||!b[l-1]||r==n-1||!b[r+1])continue;
            for(int i=l;i<=r;i++)b[i]=1;
            ans-=x;
        }
        
        cnt--;        
    }
    cout<<ans;
}

int main() {   
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    solve();
}

Compilation message (stderr)

feast.cpp: In function 'void solve()':
feast.cpp:41:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<std::pair<long long int, long long int>, std::pair<long long int, long long int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   41 |         if(idx==v.size())break;
      |            ~~~^~~~~~~~~~
feast.cpp:46:19: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   46 |             if(l>0&&b[l-1]||r<n-1&&b[r+1])continue;
      |                ~~~^~~~~~~~

• 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