Submission #169775

#	Time	Username	Problem	Language	Result	Execution time	Memory
169775		super_j6	Bootfall (IZhO17_bootfall)	C++14	28 / 100	1080 ms	13144 KiB

bootfall

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <set>
#include <map>
#include <vector>
using namespace std;
#define endl '\n'
#define pi pair<int, int>
 
const int maxn = 500, m = 250001;
int n;
int a[maxn];
map<int, int, greater<int>> dp;
set<int> cur;
int s;
 
int main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	
	cin >> n;
	
	dp[0] = 1;
	for(int i = 0; i < n; i++){
		cin >> a[i];
		s += a[i];
		
		for(auto it = dp.begin(); it != dp.end();){
			int j = it->first;
			it++;
			dp[j + a[i]] += dp[j];
		}
	}
	
	if(s % 2 || !dp[s / 2]){
		cout << 0 << endl;
		cout << endl;
		return 0;
	}
	
	for(int i = 1; i < m; i++) cur.insert(i);
	
	for(int i = 0; i < n; i++){
		for(auto it = prev(dp.end()); it != dp.begin();){
			int j = it->first;
			it--;
			if(!dp[j]) dp.erase(j);
			else dp[j + a[i]] -= dp[j];
		}
		
		for(auto it = cur.begin(); it != cur.end();){
			int x = *it;
			it++;
			if((s - a[i] + x) % 2 || dp.find((s - a[i] + x) / 2) == dp.end()) cur.erase(x);
		}
		
		for(auto it = dp.begin(); it != dp.end();){
			int j = it->first;
			it++;
			dp[j + a[i]] += dp[j];
		}
	}
	
	vector<int> ans;
	for(auto it = cur.begin(); it != cur.end(); it++) ans.push_back(*it);
	
	cout << ans.size() << endl;
	if(!ans.empty()){
		cout << ans[0];
		for(int i = 1; i < ans.size(); i++) cout << " " << ans[i];
	}
	cout << endl;
 
	return 0;
}

Compilation message (stderr)

bootfall.cpp: In function 'int main()':
bootfall.cpp:71:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 1; i < ans.size(); i++) cout << " " << ans[i];
                  ~~^~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 7 / 7
• Subtask 3: 15 / 15
• Subtask 4: 0 / 16
• Subtask 5: 0 / 21
• Subtask 6: 0 / 35