Submission #466938

#	Time	Username	Problem	Language	Result	Execution time	Memory
466938		AMO5	Discharging (NOI20_discharging)	C++17	9 / 100	1087 ms	33472 KiB

Discharging

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define ld long double
#define all(x) x.begin(),x.end()
#define sz(x) (int)x.size()
#define dbg if(0)
#define BUG(x) dbg cerr << (#x) << " is " << (x) << endl

const int mxn = (int)1e6+5;
const int64_t inf = 5e18;

void solve(){
	int n; cin>>n;
	vector<int64_t>a(n); 
	for(auto &x:a)
	{
		cin>>x;
	}
	//dp
	//when n is small
	vector<array<int64_t,2>>dp(n);
	for(int i=0; i<n; i++){
		int64_t now = a[i], res = 0, tmp = 0;
		for(int len=1,j=i; j>=0; j--,len++){
			now = max(now,a[j]);
			int64_t prev_sum = (j>0?dp[j-1][1]:(int64_t)0);
			int64_t sum = (j>0?dp[j-1][0]:(int64_t)0);
			int64_t curr = len*(now+sum)+prev_sum;
			dbg cerr<<i<<" "<<j<<" "<<sum<<" "<<now<<" "<<len<<" "<<prev_sum<<" "<<curr<<"\n";
			if(j==i)res = curr, tmp = sum+now;
			else if(curr<res){
				res = curr;
				tmp = sum+now;
			}else if(curr==res){
				tmp = min(tmp, sum+now);
			}
		}
		dp[i][0]=tmp;
		dp[i][1]=res;
		dbg cerr<<dp[i][0]<<" "<<dp[i][1]<<"\n";
	}
	cout<<dp[n-1][1]<<"\n";
}

int main(){
	ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	// int t=1; cin>>t; while(t--)
	solve();
	return 0;
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 13
• Subtask 3: 0 / 25
• Subtask 4: 0 / 11
• Subtask 5: 0 / 14
• Subtask 6: 0 / 28