Submission #33971

#	Time	Username	Problem	Language	Result	Execution time	Memory
33971		imeimi2000	Paint By Numbers (IOI16_paint)	C++14	100 / 100	1916 ms	242336 KiB

paint

#include "paint.h"
#include <algorithm>
#include <cstdlib>

using namespace std;
typedef long long llong;

int n, k;
int dp1[200001][101];
int dp2[200002][102];
int dp3[200001][101];
int sumB[200001];
int sumW[200001];
char str[200002];
vector<int> block;

string solve_puzzle(string s, vector<int> c) {
	char trans[256];
	trans['.'] = 'N';
	trans['X'] = 'B';
	trans['_'] = 'W';
	n = s.length(); k = c.size();
	block.resize(k + 1);
	for (int i = 1; i <= n; ++i) str[i] = trans[s[i - 1]];
	for (int i = 1; i <= k; ++i) block[i] = c[i - 1];
	for (int i = 1; i <= n; ++i) {
		sumB[i] = sumB[i - 1] + (str[i] == 'B');
		sumW[i] = sumW[i - 1] + (str[i] == 'W');
	}

	dp1[0][0] = true;
	for (int i = 1; i <= n; ++i) {
		dp1[i][0] = (sumB[i] == 0);
		dp1[i][1] = (i > 1 && dp1[i - 1][1] && str[i] != 'B')
			|| (i >= block[1] && sumW[i] == sumW[i - block[1]] && sumB[i - block[1]] == 0);
	}
	for (int i = 2; i <= k; ++i) {
		for (int j = block[i] + 2; j <= n; ++j) {
			dp1[j][i] = (j > 1 && str[j] != 'B' && dp1[j - 1][i])
				|| (j > block[i] + 1 && str[j - block[i]] != 'B'
				&& sumW[j - block[i]] == sumW[j] && dp1[j - block[i] - 1][i - 1]);
		}
	}

	dp2[n + 1][k + 1] = true;
	for (int i = n; i >= 1; --i) {
		dp2[i][k + 1] = (sumB[i - 1] == sumB[n]);
		dp2[i][k] = (i > 1 && dp2[i + 1][k] && str[i] != 'B')
			|| (i <= n - block[k] + 1 && sumW[i - 1] == sumW[i + block[k] - 1]
			&& sumB[i + block[k] - 1] == sumB[n]);
	}
	for (int i = k - 1; i > 0; --i) {
		for (int j = n - block[i] - 1; j > 0; --j) {
			dp2[j][i] = (j < n && str[j] != 'B' && dp2[j + 1][i])
				|| (j < n - block[i] && str[j + block[i]] != 'B'
					&& sumW[j + block[i] - 1] == sumW[j - 1] && dp2[j + block[i] + 1][i + 1]);
		}
	}

	if (k == 1) {
		for (int i = block[1]; i <= n; ++i) {
			dp3[i][1] = (sumW[i] == sumW[i - block[1]]
				&& sumB[i - block[1]] == 0 && sumB[i] == sumB[n]);
			dp3[i][1] += dp3[i - 1][1];
		}
	}
	else {
		for (int i = 1; i <= n; ++i) {
			dp3[i][k] = (i > block[k] && dp1[i - block[k] - 1][k - 1]
				&& sumW[i] == sumW[i - block[k]] && sumB[i] == sumB[n]
				&& str[i - block[k]] != 'B');
			dp3[i][k] += dp3[i - 1][k];
			dp3[i][1] = (i >= block[1] && sumW[i] == sumW[i - block[1]]
				&& sumB[i - block[1]] == 0 && i < n && dp2[i + 2][2]
				&& str[i + 1] != 'B');
			dp3[i][1] += dp3[i - 1][1];
		}
	}

	for (int i = 2; i < k; ++i) {
		for (int j = 1; j <= n; ++j) {
			dp3[j][i] = (j > block[i] && j < n && dp1[j - block[i] - 1][i - 1]
				&& dp2[j + 2][i + 1] && sumW[j] == sumW[j - block[i]]
				&& str[j - block[i]] != 'B' && str[j + 1] != 'B');
			dp3[j][i] += dp3[j - 1][i];
		}
	}

	int j;
	for (int i = 1; i <= n; ++i) {
		if (str[i] != 'N') continue;
		for (j = 0; j <= k; ++j) {
			if (dp1[i - 1][j] && dp2[i + 1][j + 1]) break;
		}
		if (j > k) str[i] = 'B';
	}
	for (int i = 1; i <= n; ++i) {
		if (str[i] != 'N') continue;
		for (j = 1; j <= k; ++j) {
			if (dp3[min(n, i + block[j] - 1)][j] - dp3[i - 1][j] != 0) break;
		}
		if (j > k) str[i] = 'W';
	}
	string ret = "";
	trans['N'] = '?';
	trans['B'] = 'X';
	trans['W'] = '_';
	for (int i = 1; i <= n; ++i) ret.push_back(trans[str[i]]);
	return ret;
}

Compilation message (stderr)

paint.cpp: In function 'std::__cxx11::string solve_puzzle(std::__cxx11::string, std::vector<int>)':
paint.cpp:24:54: warning: array subscript has type 'char' [-Wchar-subscripts]
  for (int i = 1; i <= n; ++i) str[i] = trans[s[i - 1]];
                                                      ^
paint.cpp:108:57: warning: array subscript has type 'char' [-Wchar-subscripts]
  for (int i = 1; i <= n; ++i) ret.push_back(trans[str[i]]);
                                                         ^

• Subtask 1: 7 / 7
• Subtask 2: 3 / 3
• Subtask 3: 22 / 22
• Subtask 4: 27 / 27
• Subtask 5: 21 / 21
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10