Submission #889622

#	Time	Username	Problem	Language	Result	Execution time	Memory
889622		vjudge1	Council (JOI23_council)	C++17	6 / 100	4056 ms	66636 KiB

council

#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 int long long
#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 = 3e5 + 5, inf = 1e18;

int a[N][25];
int cnt[25];
int ans[N];
int was[N], in[N];
main(){
	iostream::sync_with_stdio(false);	
    cin.tie(nullptr);
    cout.tie(nullptr);
    int n, m;
    cin >> n >> m;
    for(int i = 1; i <= n; i++){
		int x = 0;
		for(int j = 1; j <= m; j++){
			cin >> a[i][j];
			x += (a[i][j] * (1ll << (j - 1)));
			cnt[j] += (a[i][j] == 1);
		}
		in[i] = x;
	}
	
	for(int i = 1 ; i <= n; i++){
		for(int l = 1; l <= m; l++){
			cnt[l] -= (a[i][l] == 1);
		}
		
		for(int bit = 0; bit < (1 << m); bit++){
			if(!was[bit])continue;
			int res = 0;
			for(int l = 1; l <= m; l++){
				cnt[l] -= min(1ll, (bit & (1 << (l - 1))));
				res += (cnt[l] >= n / 2);
			}
			ans[i] = max(res, ans[i]);
			
			for(int l = 1; l <= m; l++){
				cnt[l] += min(1ll, (bit & (1 << (l - 1))));
			}
		}
		for(int l = 1; l <= m; l++){
			cnt[l] += (a[i][l] == 1);
		}
		was[in[i]] = 1;
	}
	
	for(int bit = 0; bit < (1 << m); bit++)was[bit] = 0;
	
	for(int i = n; i >= 1; i--){
		for(int l = 1; l <= m; l++){
			cnt[l] -= (a[i][l] == 1);
		}
		
		for(int bit = 0; bit < (1 << m); bit++){
			if(!was[bit])continue;
			int res = 0;
			for(int l = 1; l <= m; l++){
				cnt[l] -= min(1ll, (bit & (1 << (l - 1))));
				res += (cnt[l] >= n / 2);
			}
			ans[i] = max(res, ans[i]);
			
			for(int l = 1; l <= m; l++){
				cnt[l] += min(1ll, (bit & (1 << (l - 1))));
			}
		}
		for(int l = 1; l <= m; l++){
			cnt[l] += (a[i][l] == 1);
		}
		was[in[i]] = 1;
	}
	
	for(int i = 1; i <= n; i++)
		cout << ans[i] <<"\n";
}

/*
 * 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)

council.cpp:24:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   24 | main(){
      | ^~~~
council.cpp: In function 'void fp(std::string)':
council.cpp:13:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
council.cpp:13:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 8
• Subtask 2: 0 / 8
• Subtask 3: 6 / 6
• Subtask 4: 0 / 19
• Subtask 5: 0 / 15
• Subtask 6: 0 / 22
• Subtask 7: 0 / 22