oj.uz

Submission #495181

# Submission time Handle Problem Language Result Execution time Memory
495181 2021-12-18T06:11:04 Z Ierus Chessboard (IZhO18_chessboard) C++17
8 / 100
 29 ms 4652 KB 
#include<bits/stdc++.h>
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
*/
using namespace std;
#pragma GCC optimize ("unroll-loops,Ofast,O3")
#pragma GCC target("avx,avx2,fma")
#define F first
#define S second
#define sz(x) (int)x.size()
#define pb push_back
#define int long long
#define eb emplace_back
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define NFS ios_base::sync_with_stdio(0) , cin.tie(0) , cout.tie(0) ;
#define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
//#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
typedef long long ll;
const int E = 1e6+777;
const long long inf = 1e18+777;
const int N = 1e5+777;
const int MOD = 1e9+7;
vector<int> div(int x){
	vector<int> res = {1};
	for(int i = 2; i * i <= x; ++i){
		if(x % i == 0){
			res.pb(i);
			if(x / i != i)	
				res.pb(x/i);
		}
	}
	sort(all(res));
	return res;
}
struct block{
	int x1, y1, x2, y2;
	void read(){
		cin >> x1 >> y1 >> x2 >> y2;
	}
}a[N];
int n, k;
int get1(){
	int b[N][2]{};
	for(int i = 1; i <= k; ++i){
		++b[a[i].x1][a[i].y1&1];
	}
	int cnt1 = n * n / 2 + (n & 1);
	int cnt2 = n * n - cnt1;
	int sum1 = 0, sum2 = 0;
	for(int i = 1; i <= n; ++i){
		if(i & 1){
			sum1 += b[i][1];
			sum2 += b[i][0];
		}else{
			sum1 += b[i][0];
			sum2 += b[i][1];
		}
	}
	return min(cnt1 - sum1 + sum2, cnt2 - sum2 + sum1);
}
int pref[1111][1111], ar[1111][1111];
void precalc(){
	for(int l = 1; l <= k; ++l){
		ar[a[l].x1][a[l].y1] = 1;
	}
	pref[1][1] = ar[1][1];
    for(int i = 2; i <= n; i++) {
        pref[i][1] = pref[i-1][1] + ar[i][1];
    }
    for(int i = 2; i <= n; i++) {
        pref[1][i] = pref[1][i-1] + ar[1][i];
    }
    for (int i = 2; i <= n; i++) {
        for (int j = 2; j <= n; j++) {
            pref[i][j] = pref[i-1][j] + pref[i][j-1] - pref[i-1][j-1] + ar[i][j];
        }
    }
//    cerr << "array\n";
//    for(int i = 1; i <= n; ++i){
//    	for(int j = 1; j <= n; ++j){
//    		cerr << ar[i][j] << ' ';
//		}cerr << '\n';
//	}cerr << '\n';
//	cerr << "pref\n";
//    for(int i = 1; i <= n; ++i){
//    	for(int j = 1; j <= n; ++j){
//    		cerr << pref[i][j] << ' ';
//		}cerr << '\n';
//	}cerr << '\n';
}
long long query(int x1, int y1, int x2, int y2) {
    return pref[x2][y2] - pref[x1 - 1][y2] - pref[x2][y1 - 1] + pref[x1 - 1][y1 - 1];
}
int get2(vector<int> &d, int res = LLONG_MAX){
	precalc();
	for(auto x : d){
		int sum1 = 0, sum2 = 0, cnt1 = 0, cnt2 = 0;
		bool ok = 1;
		for(int i = 1; i <= n; i += x){
			for(int j = 1; j <= n; j += x){
				int x1 = i, y1 = j, x2 = i + x - 1, y2 = j + x - 1;
				int cur = query(x1, y1, x2, y2);
//				cerr << i << ' ' << j << ": " << ok << '\n';
				if(ok & 1){
					sum1 += cur;
					cnt1 += x * x;
				}else{
					sum2 += cur;
					cnt2 += x * x;
				}
				ok ^= 1;
			}
			if((n / x) & 1) ok^=1;
//			cerr <<"2i: " << i << " ok: " << ok << '\n';
		}
//		cerr << "X: " << x << " cnt1: " << cnt1 << " sum1: " << sum1 <<  " cnt2: " << cnt2 << " sum2: " << sum2 << '\n';
	res = min({res, cnt1 - sum1 + sum2, cnt2 - sum2 + sum1});
	}
	return res;
}
signed main(){auto solve=[&](){
	cin >> n >> k;
	for(int i = 1; i <= k; ++i){
		a[i].read();
	}
	vector<int> d = div(n);
//	cerr << "D: ";for(auto it : d){
//		cerr << it << ' ';
//	}cerr << '\n';
	if(sz(d) == 1){
		cout << get1() << '\n';	
	}else{
		cout << get2(d);
	}
};NFS;solve();}

Subtask #1
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1868 KB Output is correct
2 Incorrect 1 ms 676 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 3740 KB Output is correct
2 Correct 7 ms 2392 KB Output is correct
3 Correct 14 ms 3064 KB Output is correct
4 Correct 15 ms 3252 KB Output is correct
5 Correct 17 ms 3608 KB Output is correct
6 Correct 10 ms 2980 KB Output is correct
7 Correct 3 ms 2124 KB Output is correct
8 Correct 11 ms 2884 KB Output is correct
9 Correct 29 ms 4652 KB Output is correct
10 Correct 15 ms 3404 KB Output is correct

Subtask #3
0 / 15.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 972 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 16.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 972 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 3740 KB Output is correct
2 Correct 7 ms 2392 KB Output is correct
3 Correct 14 ms 3064 KB Output is correct
4 Correct 15 ms 3252 KB Output is correct
5 Correct 17 ms 3608 KB Output is correct
6 Correct 10 ms 2980 KB Output is correct
7 Correct 3 ms 2124 KB Output is correct
8 Correct 11 ms 2884 KB Output is correct
9 Correct 29 ms 4652 KB Output is correct
10 Correct 15 ms 3404 KB Output is correct
11 Incorrect 1 ms 972 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 1868 KB Output is correct
2 Incorrect 1 ms 676 KB Output isn't correct
3 Halted 0 ms 0 KB -