oj.uz

Submission #500346

# Submission time Handle Problem Language Result Execution time Memory
500346 2021-12-30T18:55:57 Z dostigator Chessboard (IZhO18_chessboard) C++14
39 / 100
 165 ms 8012 KB 
// author lox:(
#pragma GCC optimize("O3")
#pragma GCC target("popcnt")
#include <bits/stdc++.h>
using namespace std;
#define IZhO_SILVER ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define popcnt __builtin_popcount
#define all(a) a.begin(),a.end()
#define low_b lower_bound
#define up_b upper_bound
#define vii vector<pair<ll,ll>>
#define vll vector<pair<ll,ll>>
#define pii pair<ll,ll>
#define mii map<ll,ll>
#define pll pair<ll,ll>
#define mll map<ll,ll>
#define vi vector<ll>
#define vl vector<ll>
#define pb push_back
#define endl '\n'
#define Y second
#define X first
typedef long double ld;
typedef long long ll;
const long long dx[4]={1,-1,0,0},dy[4]={0,0,1,-1},col=107,N=1e6+777;
const ll mod=1e9+7,inf=1e18;
void fre_open(){freopen("file.in","r",stdin);freopen("file.out","w",stdout);}
ll binpow(ll n,ll k){if(k<0)return 0ll;if(k==0)return 1ll;if(k%2)return (binpow(n,k-1)*n)%mod;ll kk=binpow(n,k/2)%mod;return (kk*kk)%mod;}
int a[2001][2001];
int n,k;
bool isprime(long long x)
{
	if(x < 2) return 0;
	if(x == 2 || x == 3) return 1;
	if(x % 2 == 0 || x % 3 == 0) return 0;
	for(int i = 5; i * i <= n; i += 6)
		if(x % i == 0 || x % (i+2) == 0)
			return 0;
	return 1;
}
void f2()
{
	int x = n*n/2;
	int x2 = x + 1;
	for(int c = 0, i1, i2, j1, j2; c < k; ++c)
	{
		cin >> i1 >> j1 >> i2 >> j2;
		for(int i = i1; i <= i2; ++i)
			for(int j = j1; j <= j2; ++j)
			{
				if(i % 2 == j % 2) x++, x2--;
				if(i % 2 != j % 2) x2++, x--;
			}
	}

	cout << min(x, x2);
}
void solve(){
    cin>>n>>k;
    if(k==0){
        int x=n*n/2;
        for(int i=n/2; i>=1; --i)if(n%i==0)x=min(x,i*i*((n/i)*(n/i)/2));
        cout<<x;
        return;
    }
    else if(isprime(n)) {f2();return;}
    for(int i=1; i<=k; ++i){
        ll x,y,tox,toy;
        cin>>x>>y>>tox>>toy;
        a[x][y]=1;
    }
    int ans=mod-10;
    for(int d=1; d*d<=n; ++d){
        if(n%d!=0) continue;
        int res=0,res2=0;
        for(int i=1; i<=n; ++i){
            for(int j=1; j<=n; ++j){
                int x=(i+(d-1))/d;
                int y=(j+(d-1))/d;
                if((x+y)%2 && a[i][j]) ++res2;
                if((x+y)%2 && !a[i][j]) ++res;
                if(!((x+y)%2) && a[i][j]) ++res;
                if(!((x+y)%2) && !a[i][j]) ++res2;
            }
        }
        ans=min({ans,res,res2});
        //cout<<d<<' '<<res<<' '<<res2<<endl;
        int f=n/d;
        res=0,res2=0;
        for(int i=1; i<=n; ++i){
            for(int j=1; j<=n; ++j){
                int x=(i+(f-1))/f;
                int y=(j+(f-1))/f;
                if((x+y)%2 && a[i][j]) ++res2;
                if((x+y)%2 && !a[i][j]) ++res;
                if(!((x+y)%2) && a[i][j]) ++res;
                if(!((x+y)%2) && !a[i][j]) ++res2;
            }
        }
        if(d==1){
            ans=min(ans,max(res,res2));
            continue;
        }
        ans=min({ans,res,res2});
        //cout<<d<<' '<<res<<' '<<res2<<endl;
    }
    cout<<ans<<endl;
}
/*
6 8
3 3 3 3
1 2 1 2
3 4 3 4
5 5 5 5
4 3 4 3
4 4 4 4
2 1 2 1
3 6 3 6*/
int main() {
    //fre_open();
    IZhO_SILVER;
    ll tt=1;
    //cin>>tt;
    while(tt--) solve();
}

Compilation message

chessboard.cpp: In function 'void fre_open()':
chessboard.cpp:27:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 | void fre_open(){freopen("file.in","r",stdin);freopen("file.out","w",stdout);}
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
chessboard.cpp:27:53: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 | void fre_open(){freopen("file.in","r",stdin);freopen("file.out","w",stdout);}
      |                                              ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Incorrect 17 ms 316 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 596 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 596 KB Output is correct
4 Correct 1 ms 596 KB Output is correct
5 Correct 1 ms 596 KB Output is correct
6 Correct 1 ms 596 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 724 KB Output is correct
10 Correct 0 ms 204 KB Output is correct
11 Correct 1 ms 588 KB Output is correct
12 Correct 0 ms 204 KB Output is correct
13 Correct 1 ms 588 KB Output is correct
14 Correct 1 ms 588 KB Output is correct
15 Correct 1 ms 460 KB Output is correct

Subtask #4
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 596 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 596 KB Output is correct
4 Correct 1 ms 596 KB Output is correct
5 Correct 1 ms 596 KB Output is correct
6 Correct 1 ms 596 KB Output is correct
7 Correct 1 ms 596 KB Output is correct
8 Correct 1 ms 468 KB Output is correct
9 Correct 1 ms 724 KB Output is correct
10 Correct 0 ms 204 KB Output is correct
11 Correct 1 ms 588 KB Output is correct
12 Correct 0 ms 204 KB Output is correct
13 Correct 1 ms 588 KB Output is correct
14 Correct 1 ms 588 KB Output is correct
15 Correct 1 ms 460 KB Output is correct
16 Correct 29 ms 7404 KB Output is correct
17 Correct 22 ms 320 KB Output is correct
18 Correct 48 ms 7992 KB Output is correct
19 Correct 161 ms 7672 KB Output is correct
20 Correct 165 ms 7668 KB Output is correct
21 Correct 18 ms 204 KB Output is correct
22 Correct 85 ms 1868 KB Output is correct
23 Correct 53 ms 7700 KB Output is correct
24 Correct 46 ms 8012 KB Output is correct
25 Correct 46 ms 6988 KB Output is correct
26 Correct 38 ms 7600 KB Output is correct
27 Correct 49 ms 7688 KB Output is correct
28 Correct 45 ms 7688 KB Output is correct
29 Correct 8 ms 204 KB Output is correct
30 Correct 23 ms 5452 KB Output is correct

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 17 ms 316 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 204 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 0 ms 204 KB Output is correct
8 Correct 0 ms 204 KB Output is correct
9 Incorrect 17 ms 316 KB Output isn't correct
10 Halted 0 ms 0 KB -