Submission #1106532

#	Time	Username	Problem	Language	Result	Execution time	Memory
1106532		Octagons	Mosaic (IOI24_mosaic)	C++17	100 / 100	333 ms	26188 KiB

mosaic

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2e5+2, lim = 3;
int n, q, a[lim][N], b[N][lim];
vector<int> v, v2;
ll pref[N], pref2[N];
ll geta(int rw, int l, int r) {
	return a[rw][r] - (l ? a[rw][l-1] : 0);
}
 
ll getb(int col, int l, int r) {
	l = max(l, lim-1);
	if (l > r)return 0;
	return b[r][col] - b[l-1][col];
}
 
ll getp(int l, int r) {
	return pref[r] - (l ? pref[l-1] : 0ll);
}
 
ll getp2(int l, int r) {
	return pref2[r] - (l ? pref2[l-1] : 0ll);
}
 
ll get(int x, int y) {
	if (x < 0 || y < 0)return 0;
	ll ret = 0;
	for (int i = 0; i+1 < lim && i <= x; i++) {
		ret += geta(i, 0, y);
	}
	for (int i = 0; i+1 < lim && i <= y; i++) {
		ret += getb(i, 0, x);
	}
	if (x+1 < lim || y+1 < lim)return ret;
	x -= (lim - 1), y -= (lim - 1);
	int id = upper_bound(v.begin(), v.end(), y+1) - v.begin();
	if (id) {
		--id;
		int id2 = upper_bound(v.begin(), v.end(), y-x) - v.begin();
		--id2;
		id2 = min(id2, id);
		if (id2 == -1) {
			ret += ll(id+1) * ll(y+1) - getp(0, id);
		} else {
			ret += ll(id2+1) * ll(x+1);
			if (id2 != id)ret += ll(id-id2) * ll(y+1) - getp(id2+1, id);
		}
	}
	swap(x, y);
	id = upper_bound(v2.begin(), v2.end(), y+1) - v2.begin();
	if (id) {
		--id;
		int id2 = upper_bound(v2.begin(), v2.end(), y-x) - v2.begin();
		--id2;
		id2 = min(id2, id);
		if (id2 == -1) {
			ret += ll(id+1) * ll(y+1) - getp2(0, id);
		} else {
			ret += ll(id2+1) * ll(x+1);
			if (id2 != id)ret += ll(id-id2) * ll(y+1) - getp2(id2+1, id);
		}
	}
	return ret;
}
 
vector<long long> mosaic(vector<int> X, vector<int> Y, vector<int> T, vector<int> B, vector<int> L, vector<int> R) {
	q = L.size();
	n = X.size();
	v.clear();
	v2.clear();
	vector<long long> ret(q);
	for (int i = 0; i < n; i++) {
		a[0][i] = X[i];
		b[i][0] = Y[i];
		if (i < lim) {
			b[0][i] = X[i];
			a[i][0] = Y[i];
		}
	}
	for (int i = 1; i < lim; i++) {
		for (int j = 1; j < n; j++) {
			a[i][j] = (a[i-1][j] || a[i][j-1] ? 0 : 1);
		}
	}
	for (int i = 0; i < lim; i++) {
		for (int j = 1; j < n; j++) {
			if (i == lim-1) {
				continue;
			}
			a[i][j] += a[i][j-1];
		}
	}
	for (int i = 1; i < n; i++) {
		for (int j = 1; j < lim; j++) {
			b[i][j] = (b[i-1][j] || b[i][j-1] ? 0 : 1);
		}
	}
	for (int i = 1; i < n; i++) {
		for (int j = 0; j < lim; j++) {
			if (j == lim-1) {
				continue;
			}
			b[i][j] += b[i-1][j];
		}
	}
	for (int i = lim-1; i < n; i++) {
		if (a[lim-1][i]) {
			v.push_back(i - (lim - 1));
		}
	}
	for (int j = lim; j < n; j++) {
		if (b[j][lim-1]) {
			v2.push_back(j - (lim - 1));
		}
	}
	ll sm = 0;
	for (int i = 0; i < v.size(); i++) {
		sm += ll(v[i]);
		pref[i] = sm;
	}
	sm = 0;
	for (int i = 0; i < v2.size(); i++) {
		sm += ll(v2[i]);
		pref2[i] = sm;
	}
	for (int i = 0; i < q; i++) {
		int x = T[i], y = L[i];
		int x2 = B[i], y2 = R[i];
		ret[i] = get(x2, y2) - get(x-1, y2) - get(x2, y-1) + get(x-1, y-1);
	}
	return ret;
}

Compilation message (stderr)

mosaic.cpp: In function 'std::vector<long long int> mosaic(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
mosaic.cpp:118:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  118 |  for (int i = 0; i < v.size(); i++) {
      |                  ~~^~~~~~~~~~
mosaic.cpp:123:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  123 |  for (int i = 0; i < v2.size(); i++) {
      |                  ~~^~~~~~~~~~~

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 7 / 7
• Subtask 4: 10 / 10
• Subtask 5: 8 / 8
• Subtask 6: 22 / 22
• Subtask 7: 19 / 19
• Subtask 8: 22 / 22