Submission #1022997

#	Time	Username	Problem	Language	Result	Execution time	Memory
1022997		AmirAli_H1	Paint By Numbers (IOI16_paint)	C++17	100 / 100	260 ms	46020 KiB

paint

// In the name of Allah

#include <bits/stdc++.h>
#include "paint.h"
using namespace std;

typedef		long long int			ll;
typedef		long double				ld;
typedef		pair<int, int>			pii;
typedef		pair<ll, ll>			pll;
typedef		complex<ld>				cld;

#define		all(x)					(x).begin(),(x).end()
#define		len(x)					((ll) (x).size())
#define		F						first
#define		S						second
#define		pb						push_back
#define		sep						' '
#define		endl					'\n'
#define		Mp						make_pair
#define		kill(x)					cout << x << '\n', exit(0)
#define		set_dec(x)				cout << fixed << setprecision(x);
#define		file_io(x,y)			freopen(x, "r", stdin); freopen(y, "w", stdout);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int maxn = 2e5 + 7;
const int maxk = 100 + 4;

int n, k;
int A[maxn], val[maxk];
int sm0[maxn], sm1[maxn];
bool dp1[maxn][maxk], dp2[maxn][maxk];
int ok0[maxn], ok1[maxn];

string solve_puzzle(string s, vector<int> c) {
	n = len(s); k = len(c);
	for (int i = 1; i <= n; i++) {
		if (s[i - 1] == 'X') A[i] = 1;
		else if (s[i - 1] == '_') A[i] = 0;
		else A[i] = -1;
		sm0[i] = sm0[i - 1] + (A[i] == 0);
		sm1[i] = sm1[i - 1] + (A[i] == 1);
	}
	for (int i = 1; i <= k; i++) val[i] = c[i - 1];
	
	dp1[0][0] = 1;
	for (int i = 1; i <= n; i++) {
		for (int j = 0; j <= k; j++) {
			if (A[i] != 1) dp1[i][j] = dp1[i - 1][j];
			else dp1[i][j] = 0;
			
			if (j >= 1 && i - val[j] >= 0) {
				if (sm0[i] - sm0[i - val[j]] == 0) {
					if (i - val[j] == 0) dp1[i][j] |= dp1[i - val[j]][j - 1];
					else if (A[i - val[j]] != 1) dp1[i][j] |= dp1[i - val[j] - 1][j - 1];
				}
			}
		}
	}
	
	dp2[n + 1][k + 1] = 1;
	for (int i = n; i >= 1; i--) {
		for (int j = k + 1; j >= 1; j--) {
			if (A[i] != 1) dp2[i][j] = dp2[i + 1][j];
			else dp2[i][j] = 0;
			
			if (j <= k && i + val[j] - 1 <= n) {
				if (sm0[i + val[j] - 1] - sm0[i - 1] == 0) {
					if (i + val[j] == n + 1) dp2[i][j] |= dp2[i + val[j]][j + 1];
					else if (A[i + val[j]] != 1) dp2[i][j] |= dp2[i + val[j] + 1][j + 1];
				}
			}
		}
	}
	
	for (int i = 1; i <= n; i++) {
		for (int j = 0; j <= k; j++) {
			if (dp1[i - 1][j] && dp2[i + 1][j + 1]) {
				ok0[i]++; ok0[i + 1]--;
			}
		}
	}
	
	for (int j = 1; j <= k; j++) {
		for (int i = val[j]; i <= n; i++) {
			if (sm0[i] - sm0[i - val[j]] != 0) continue;
			if (i + 1 <= n && A[i + 1] == 1) continue;
			if (i - val[j] >= 1 && A[i - val[j]] == 1) continue;
			int j1 = max(i - val[j] - 1, 0);
			int j2 = min(i + 2, n + 1);
			if (dp1[j1][j - 1] && dp2[j2][j + 1]) {
				ok1[i - val[j] + 1]++; ok1[i + 1]--;
			}
		}
	}
	
	string res = s;
	for (int i = 1; i <= n; i++) {
		ok0[i] += ok0[i - 1]; ok1[i] += ok1[i - 1];
		if (res[i - 1] == '.') {
			if (ok0[i] > 0 && ok1[i] > 0) res[i - 1] = '?';
			else if (ok0[i] > 0) res[i - 1] = '_';
			else res[i - 1] = 'X';
		}
	}
	return res;
}

• 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