Submission #671939

#	Time	Username	Problem	Language	Result	Execution time	Memory
671939		Baytoro	K blocks (IZhO14_blocks)	C++17	0 / 100	1 ms	340 KiB

blocks

#include <bits/stdc++.h>
using namespace std;
#define ios ios::sync_with_stdio(false); cin.tie(NULL);
#define pb push_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define fr first
#define sc second
#define int long long
#define endl '\n'
void fopn(string name){
	freopen((name+".in").c_str(),"r",stdin);
	freopen((name+".out").c_str(),"w",stdout);
}
const int INF=1e18,mod=1e9+7;
int n,k;
int dp[100005][105],a[100005];
void solve(){
	cin>>n>>k;
	for(int i=1;i<=n;i++)
		cin>>a[i];
	for(int i=1;i<=n;i++){
		dp[i][1]=max(dp[i-1][1],a[i]);
	}
	for(int i=1;i<=n;i++)
		for(int j=2;j<=k;j++)
			dp[i][j]=INF;
	stack<pair<int,int>> st;
	for(int i=2;i<=k;i++){
		for(int j=i;j<=n;j++){
			int tmp=dp[j-1][i-1];
			while(!st.empty() && (st.top().sc<=a[j])){
				tmp=min(tmp,st.top().sc);
				st.pop();
			}
			if(st.empty() || st.top().fr+st.top().sc>=tmp+a[j])
				st.push({a[j],tmp});
			dp[j][i]=max(tmp+a[j],st.top().fr+st.top().sc);
		}
	}
	cout<<dp[n][k];
}
main(){
	ios;
	int T=1;
	//cin>>T;
	while(T--){
		solve();
	}
}

Compilation message (stderr)

blocks.cpp:43:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   43 | main(){
      | ^~~~
blocks.cpp: In function 'void fopn(std::string)':
blocks.cpp:12:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |  freopen((name+".in").c_str(),"r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
blocks.cpp:13:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |  freopen((name+".out").c_str(),"w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 14
• Subtask 2: 0 / 18
• Subtask 3: 0 / 21
• Subtask 4: 0 / 47