Submission #495045

#	Time	Username	Problem	Language	Result	Execution time	Memory
495045		Ziel	Chessboard (IZhO18_chessboard)	C++17	39 / 100	87 ms	6312 KiB

chessboard

/**
 * LES GREATEABLES BRO TEAM
**/

#include <bits/stdc++.h>

using namespace std;

using ll = long long;
#define sz(x) (int)x.size()
const bool FLAG = false;
void setIO(const string &f = "");

string to_string(const string s) {
	return '"' + s + '"';
}
string to_string(const char c) {
 	return char(39) + string(1, c) + char(39);
}
string to_string(const char* s) {
 	return to_string(string(s));
}
string to_string(bool f) {
	return (f ? "true" : "false");
}
template<class A, class B>
string to_string(const pair<A, B> x) {
	return "(" + to_string(x.first) + ", " + to_string(x.second) + ")";
}
template<class A, class B, class C>
string to_string(const tuple<A, B, C> x) {
	return "(" + to_string(get<0>(x)) + ", " + to_string(get<1>(x)) + ", " + to_string(get<2>(x)) + ")";
}
template<class A, class B, class C, class D>
string to_string(const tuple<A, B, C, D> x) {
	return "(" + to_string(get<0>(x)) + ", " + to_string(get<1>(x)) + ", " + to_string(get<2>(x)) + ", " + to_string(get<3>(x)) + ")";
}
template<class T>
string to_string(const T v) {
	string res = "{"; bool f = true;
	for (auto x: v)
		res += (f ? to_string(x) : ", " + to_string(x)), f = false;
	return res + "}";
}
void debug_args() { cerr << "]\n"; }
template<class H, class... T>
void debug_args(H x, T... y) {
	cerr << to_string(x);
	if (sizeof... (y))
	cerr << ", ";
	debug_args(y...);
}

#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]: [", debug_args(__VA_ARGS__);
#else
#define debug(...) 47
#endif

void solve() {
    int n, k;
    cin >> n >> k;
    vector<int> up(k + 1), left(k + 1), down(k + 1), right(k + 1);
    bool flag = 1;
    vector<vector<int>> a(1020, vector<int>(1020));
    for (int i = 1; i <= k; i++) {
    	cin >> up[i] >> left[i] >> down[i] >> right[i];
    	if (up[i] != down[i] || left[i] != right[i])
    		flag = 0;
    	if (n <= 1000) {
    		for (int ii = up[i]; ii <= down[i]; ii++)
    			for (int jj = left[i]; jj <= right[i]; jj++)
    				a[ii][jj] = 1;
    	}
    }

    if (n <= 1000) {
    	int ans = n * n * 3;
    	for (int len = 1; len * len <= n; len++) {
    		if (n % len == 0) {
    			int turn = 0, cur = 0, st_turn = 0;
    			for (int i = 1; i <= n; i += len) {
    				turn = st_turn;
 					st_turn ^= 1;
    				for (int j = 1; j <= n; j += len) {
    					for (int ii = i; ii < i + len; ii++) {
    						for (int jj = j; jj < j + len; jj++) {
    							if (a[ii][jj] != turn)
    								cur++;
    						}
    					}
    					turn ^= 1;
    				}
    			}
    			ans = min(ans, cur);

    			cur = 0, st_turn = 1;
    			for (int i = 1; i <= n; i += len) {
    				turn = st_turn;
 					st_turn ^= 1;
    				for (int j = 1; j <= n; j += len) {
    					for (int ii = i; ii < i + len; ii++) {
    						for (int jj = j; jj < j + len; jj++) {
    							if (a[ii][jj] != turn)
    								cur++;
    						}
    					}
    					turn ^= 1;
    				}
    			}
    			ans = min(ans, cur);


				if (len != 1) {
	    			int len2 = n / len;
    				st_turn = 0, cur = 0;
    				for (int i = 1; i <= n; i += len2) {
    					turn = st_turn;
 						st_turn ^= 1;
    					for (int j = 1; j <= n; j += len2) {
    						for (int ii = i; ii < i + len2; ii++) {
    							for (int jj = j; jj < j + len2; jj++) {
    								if (a[ii][jj] != turn)
    									cur++;
	    						}
    						}
    						turn ^= 1;
    					}
    				}
	    			ans = min(ans, cur);

    				cur = 0, st_turn = 1;
    				for (int i = 1; i <= n; i += len2) {
    					turn = st_turn;
 						st_turn ^= 1;
    					for (int j = 1; j <= n; j += len2) {
    						for (int ii = i; ii < i + len2; ii++) {
    							for (int jj = j; jj < j + len2; jj++) {
    								if (a[ii][jj] != turn)
    									cur++;
	    						}
    						}
    						turn ^= 1;
    					}
    				}
	    			ans = min(ans, cur);
				}
    		}
    	}
    	cout << ans;
    }

/*
    else if (flag) {
    	for (int i = 1; i <= k; i++) {
    		a[up[i]][left[i]] = 1;
    	}
    }*/
}

signed main() {
    setIO();
    
    int tt = 1;
    if (FLAG) {
    	cin >> tt;
    }
    while (tt--) {
    	solve();
    }
    
    return 0;
}

void setIO(const string &f) {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (fopen((f + ".in").c_str(), "r")) {
        freopen((f + ".in").c_str(), "r", stdin);
        freopen((f + ".out").c_str(), "w", stdout);
    }
}

Compilation message (stderr)

chessboard.cpp: In function 'void solve()':
chessboard.cpp:64:10: warning: variable 'flag' set but not used [-Wunused-but-set-variable]
   64 |     bool flag = 1;
      |          ^~~~
chessboard.cpp: In function 'void setIO(const string&)':
chessboard.cpp:179:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  179 |         freopen((f + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
chessboard.cpp:180:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  180 |         freopen((f + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 0 / 8
• Subtask 3: 15 / 15
• Subtask 4: 16 / 16
• Subtask 5: 0 / 23
• Subtask 6: 0 / 30