oj.uz

Submission #495158

# Submission time Handle Problem Language Result Execution time Memory
495158 2021-12-18T05:53:44 Z armashka Chessboard (IZhO18_chessboard) C++17
31 / 100
 65 ms 3388 KB 
#include <bits/stdc++.h>
 
//#pragma comment(linker, "/stack:200000000")
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
 
#define fast ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
#define all(v) v.begin(),v.end()
#define pb push_back
#define sz size()
#define ft first
#define sd second
 
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
typedef unsigned long long ull;
 
const int N = 1e6 + 5;
const ll M = 1e8;
const ll inf = 1e9;
const ll mod = 1e9;
const double Pi = acos(-1); 
 
ll binpow(ll x, ll ti) { ll res = 1;while (ti){if(ti & 1)res *= x;x *= x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll binmul(ll x, ll ti) { ll res = 0;while (ti){if(ti & 1)res += x;x += x;ti >>= 1; x %= mod; res %= mod;} return res;}
ll nok(ll a, ll b) { return (a*b)/__gcd(abs(a),abs(b)) * (a*b > 0 ? 1 : -1); }
bool odd(ll n) { return (n % 2 == 1); }
bool even(ll n) { return (n % 2 == 0); }            
                     
struct node {
	ll x1, y1, x2, y2;
};
                                               
ll n, k, ans = inf;
bool bl[1005][1005];
node que[100005]; 
 
void check(int razmer) {
	ll cnt = 0;
	for (int i = 1; i <= n; ++ i) {
		for (int j = 1; j <= n; ++ j) {
			int num = ((i + razmer - 1) / razmer) + ((j + razmer - 1) / razmer);
			if (even(num) && !bl[i][j]) ++ cnt;
			if (odd(num) && bl[i][j]) ++ cnt; 
		}
	}
	//cout << razmer << " " << min(cnt, n * n - cnt) << "\n";
	ans = min(ans, min(cnt, n * n - cnt));
	return;
}
 
const void solve(/*Armashka*/) {
	cin >> n >> k;
	ll c1 = (n * n) / 2, c2 = (n * n) - c1, cnt1 = 0, cnt2 = 0;
	bool ok = 1;
	for (int i = 1; i <= k; ++ i) {
		ll x1, y1, x2, y2;
		cin >> x1 >> y1 >> x2 >> y2;
		que[i] = {x1, y1, x2, y2};
		if (x1 % 2 == y1 % 2) ++ cnt2;
		else ++ cnt1;
		if (x1 != x2 || y1 != y2) ok = 0;
	}
	if (k == 0) {
		cout << (n * n) - (n * n / 2) << "\n";
		return;
	}
	if (ok && k > 0) {
		vector <ll> v;
		for (int i = 1; i * i <= n; ++ i) {
			if (n % i == 0) {
				v.pb(i);
				if (n / i != i && i > 1) v.pb(n / i);
			}
		}
		for (int j = 0; j < v.sz; ++ j) {
			ll cnt1 = 0, cnt2 = 0;
			for (int i = 1; i <= k; ++ i) {                                                       
				ll num = (que[i].x1 + v[j] - 1) / v[j] + (que[i].y1 + v[j] - 1) / v[j];
				if (odd(num)) ++ cnt1;
				else ++ cnt2;
			}
			//cout << v[j] << " " << (n * n / (v[j] * v[j])) << " " << cnt1 << " " << cnt2 << "\n";
			ll res = (n * n / (v[j] * v[j] * 2) * v[j] * v[j]) - cnt1 + cnt2;
			ans = min(ans, min(res, n * n - res));
		}
		cout << ans << "\n";
		return;
	}
	for (int i = 1; i <= k; ++ i) {
		for (int j = que[i].x1; j <= que[i].x2; ++ j) {
			for (int h = que[i].y1; h <= que[i].y2; ++ h) bl[j][h] = 1;
		}
	}
	for (int i = 1; i * i <= n; ++ i) {
		if (n % i == 0) {
			check(i);
			if (n / i != i && i > 1) check(n / i);
		}
	}
	cout << ans << "\n";
}
 
signed main() {
    fast;
	//freopen("divide.in", "r", stdin);
	//freopen("divide.out", "w", stdout);
    int tt = 1;
    //cin >> tt;
    while (tt --) {
    	solve();
	}
}
 
/*
 
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
 
*/
 
/*
9 12
1 9 4
1 2 5
2 3 7
2 4 3
4 3 6
3 6 4
8 7 10
6 7 5
5 8 1
9 5 7
5 4 12
6 8 2
2
4 7
5
1 6
5 3
4 8
5 8
1 5
 
*/

Compilation message

chessboard.cpp: In function 'const void solve()':
chessboard.cpp:77:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   77 |   for (int j = 0; j < v.sz; ++ j) {
      |                     ^
chessboard.cpp:55:23: warning: unused variable 'c2' [-Wunused-variable]
   55 |  ll c1 = (n * n) / 2, c2 = (n * n) - c1, cnt1 = 0, cnt2 = 0;
      |                       ^~

Subtask #1
0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 204 KB Output is correct
2 Incorrect 0 ms 204 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #2
0 / 8.0

# Verdict Execution time Memory Grader output
1 Incorrect 24 ms 2244 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 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 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 336 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 204 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct

Subtask #4
16.0 / 16.0

# 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 1 ms 332 KB Output is correct
5 Correct 1 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 1 ms 336 KB Output is correct
9 Correct 0 ms 332 KB Output is correct
10 Correct 0 ms 204 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 8 ms 1100 KB Output is correct
17 Correct 24 ms 2924 KB Output is correct
18 Correct 29 ms 3344 KB Output is correct
19 Correct 59 ms 2980 KB Output is correct
20 Correct 65 ms 3388 KB Output is correct
21 Correct 21 ms 2848 KB Output is correct
22 Correct 1 ms 332 KB Output is correct
23 Correct 15 ms 1596 KB Output is correct
24 Correct 26 ms 3020 KB Output is correct
25 Correct 4 ms 460 KB Output is correct
26 Correct 21 ms 2072 KB Output is correct
27 Correct 25 ms 2320 KB Output is correct
28 Correct 26 ms 3268 KB Output is correct
29 Correct 11 ms 1360 KB Output is correct
30 Correct 1 ms 332 KB Output is correct

Subtask #5
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 24 ms 2244 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 Incorrect 0 ms 204 KB Output isn't correct
3 Halted 0 ms 0 KB -