oj.uz

Submission #495157

# Submission time Handle Problem Language Result Execution time Memory
495157 2021-12-18T05:52:13 Z armashka Chessboard (IZhO18_chessboard) C++17
31 / 100
 71 ms 3392 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 / 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 1 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 22 ms 2376 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 316 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 324 KB Output is correct
5 Correct 1 ms 328 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 328 KB Output is correct
8 Correct 1 ms 324 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 316 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 336 KB Output is correct
14 Correct 1 ms 336 KB Output is correct
15 Correct 1 ms 336 KB Output is correct

Subtask #4
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 316 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 324 KB Output is correct
5 Correct 1 ms 328 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 1 ms 328 KB Output is correct
8 Correct 1 ms 324 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 1 ms 316 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 336 KB Output is correct
14 Correct 1 ms 336 KB Output is correct
15 Correct 1 ms 336 KB Output is correct
16 Correct 10 ms 1104 KB Output is correct
17 Correct 24 ms 2948 KB Output is correct
18 Correct 44 ms 3276 KB Output is correct
19 Correct 65 ms 3064 KB Output is correct
20 Correct 71 ms 3392 KB Output is correct
21 Correct 20 ms 2768 KB Output is correct
22 Correct 0 ms 208 KB Output is correct
23 Correct 17 ms 1624 KB Output is correct
24 Correct 37 ms 3052 KB Output is correct
25 Correct 3 ms 588 KB Output is correct
26 Correct 17 ms 2000 KB Output is correct
27 Correct 26 ms 2400 KB Output is correct
28 Correct 54 ms 3252 KB Output is correct
29 Correct 10 ms 1240 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 22 ms 2376 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #6
0 / 30.0

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