Submission #285466

#	Time	Username	Problem	Language	Result	Execution time	Memory
285466		arnold518	Discharging (NOI20_discharging)	C++14	47 / 100	1056 ms	17856 KiB

Discharging

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

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 1e6;
const ll INF = 1e15;

int N;
ll dp[MAXN+10], A[MAXN+10];

int main()
{
	scanf("%d", &N);
	for(int i=1; i<=N; i++) scanf("%lld", &A[i]);
	reverse(A+1, A+N+1);
	
	A[0]=INF;

	vector<int> S;
	S.push_back(0);
	for(int i=1; i<=N; i++)
	{
		while(!S.empty() && A[S.back()]<=A[i]) S.pop_back();
		S.push_back(i);
	}

	for(int i=1; i<S.size(); i++) 
	{
		dp[i]=INF;
		for(int j=0; j<i; j++)
		{
			dp[i]=min(dp[i], dp[j]+A[S[j+1]]*S[i]);
		}
	}
	printf("%lld\n", dp[S.size()-1]);
}

Compilation message (stderr)

Discharging.cpp: In function 'int main()':
Discharging.cpp:30:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |  for(int i=1; i<S.size(); i++)
      |               ~^~~~~~~~~
Discharging.cpp:16:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   16 |  scanf("%d", &N);
      |  ~~~~~^~~~~~~~~~
Discharging.cpp:17:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   17 |  for(int i=1; i<=N; i++) scanf("%lld", &A[i]);
      |                          ~~~~~^~~~~~~~~~~~~~~

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