Submission #943274

#	Time	Username	Problem	Language	Result	Execution time	Memory
943274		vjudge1	Toys (CEOI18_toy)	C++17	100 / 100	4577 ms	80372 KiB

toy

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
 
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define rnd(l, r) uniform_int_distribution<int>(l, r)(rng)
 
using namespace std;
 
void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);} 
int pow(int a,int b,int m){int ans=1;while(b){if(b&1){ans=(ans*a)%m;}b>>=1;a=(a*a)%m;}return ans;}
int binpow(int a,int b){int ans=1;while(b){if(b&1){ans=(ans*a);}b>>=1;a=(a*a);}return ans;}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
const int N = 31624;

set <int> ans;
vector <int> pr;
int p[N];

unordered_map <int, unordered_map<int, bool> > mp;
unordered_map <int, vector <int> > d;

int sum;

void calc(int x){
	if(x == 1){
		ans.insert(sum);
		return;
	}
	if(mp[x][sum] == 1)return;
	mp[x][sum] = 1;
	vector <pair <int,int> > fact;
	vector <int> div = {1};
	int A = x;
	if(!d.count(x)){
		for(auto p : pr){
			if(p > x)break;
			int cnt = 0;
			while(x % p == 0){
				x /= p;
					cnt++;
			}
			if(cnt != 0)
				fact.pb({p, cnt});
		}
		if(x != 1)
			fact.pb({x, 1});
		 for (auto [p,k] : fact)
			for (int i = 1, sz = div.size(); i <= k; i++)
				for (int i = 1; i <= sz; i++)
						div.push_back(div[div.size()-sz]*p);
		d[A] = div;
	}else
		div = d[x];
	for(auto xx : div){
		if(xx != 1){
			sum = sum+xx-1;
			calc(A / xx);
			sum = sum - xx + 1;
		}
	}

}
main(){
	iostream::sync_with_stdio	(false);	
    cin.tie(nullptr);
    cout.tie(nullptr);
    for(int i = 2; i < N - 1; i++){
		if(p[i])continue;
		pr.pb(i);
		for(int j = i * i; j < N - 1; j += i){
			p[j] = 1;
		}
	}
    int n;
    cin >> n;
    calc(n);
    cout << ans.size() << endl;
    for(auto x : ans)
		cout << x <<" ";
}	
/*
 * Before implementing the problem:
	
	Do I understand the problem correctly?
	Which places are tricky? What do I need to remember to implement them correctly?
	Which place is the heaviest by implementation? Can I do it simpler?
	Which place is the slowest? Where do I need to be careful about constant factors and where I can choose slower but simpler implementation?
	----------------------------------
	If not AC:
 
	Did you remember to do everything to handle the tricky places you thought about before?
	Is the solution correct?
	Do I understand the problem correctly?
	----------------------------------
	If you have a test on which the solution gives wrong answer:
 
	Is the solution doing what it was supposed to do?
	Is the problem in the code or in the idea?
*/

Compilation message (stderr)

toy.cpp:69:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   69 | main(){
      | ^~~~
toy.cpp: In function 'void fp(std::string)':
toy.cpp:14:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
toy.cpp:14:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 19 / 19
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 20 / 20
• Subtask 5: 21 / 21