Submission #1038450

#	Time	Username	Problem	Language	Result	Execution time	Memory
1038450		PM1	Watermelon (INOI20_watermelon)	C++17	0 / 100	15 ms	9564 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define fr first
#define sc second
#define ll long long
const int mxn=1e5+5;
int n,a[mxn],b[mxn],k,L[mxn],R[mxn],sz[mxn];
vector<int>g[mxn],par[mxn];
set<int>s;
void solve(int m){
	if(s.size()==0 && m<n+1){
		cout<<-1;
		exit(0);
	}
	if(m==n+1){
		k--;
		if(k==0){
			for(int i=1;i<=n;i++)
				cout<<a[i]<<" ";
			exit(0);	
		}
		return ;
	}
	vector<int>v;
	for(auto i:s){
		v.push_back(i);
		if(v.size()==10)
			break;
	}
	for(auto i:v){
		a[i]=m;
		s.erase(i);
		for(auto j:par[i]){
			sz[j]--;
			if(sz[j]==0)
				s.insert(j);
		}
	
		solve(m+1);

		s.insert(i);
		for(auto j:par[i]){
			sz[j]++;
			if(sz[j]==1)
				s.erase(j);
		}
	}

}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin>>n>>k;
	int cnt=0;
	vector<int>hey;
	for(int i=1;i<=n;i++){
		cin>>b[i];
		if(b[i]==-1)hey.push_back(i);
	}
	if(b[n]!=-1){
		cout<<-1;
		return 0;
	}
	for(int i=1;i<hey.size();i++){
		L[hey[i]]=hey[i-1];
	}
	for(int i=0;i<hey.size();i++){
		int l=(i==0)?1:hey[i-1]+1;
		vector<int>v;
		for(;l<hey[i];l++){
			par[l].push_back(hey[i]);
			g[hey[i]].push_back(l);
			while(v.size() && b[v.back()]<=b[l]){
				R[v.back()]=l;
				v.pop_back();
			}
			if(v.size())
				L[l]=v.back();
			v.push_back(l);
		}
	}
	for(int i=1;i<=n;i++){
		if(L[i]!=0){
			par[i].push_back(L[i]);
			g[L[i]].push_back(i);
		}
		if(R[i]!=0){
			par[i].push_back(R[i]);
			g[R[i]].push_back(i);
		}
	}
	for(int i=1;i<=n;i++){
	//	cout<<L[i]<<" "<<R[i]<<'\n';
		if(b[i]!=-1 ){
			int mx=0;
			for(int j=i+1;j<R[i];j++)
				mx=max(mx,b[j]);
			if(mx+1!=b[i]){
				cout<<-1;
				return 0;
			}
			
		}
	}
	for(int i=1;i<=n;i++){
		sz[i]=g[i].size();
		if(sz[i]==0)
			s.insert(i);
	}
	solve(1);
	cout<<-1;
	return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:65:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   65 |  for(int i=1;i<hey.size();i++){
      |              ~^~~~~~~~~~~
Main.cpp:68:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |  for(int i=0;i<hey.size();i++){
      |              ~^~~~~~~~~~~
Main.cpp:55:6: warning: unused variable 'cnt' [-Wunused-variable]
   55 |  int cnt=0;
      |      ^~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 25
• Subtask 3: 0 / 31
• Subtask 4: 0 / 18
• Subtask 5: 0 / 19