Submission #514113

#	Time	Username	Problem	Language	Result	Execution time	Memory
514113		tabr	Paint By Numbers (IOI16_paint)	C++17	100 / 100	1016 ms	240676 KiB

paint

#include <bits/stdc++.h>
using namespace std;
#ifdef tabr
#include "library/debug.cpp"
#else
#define debug(...)
#endif

string solve_puzzle(string s, vector<int> c) {
    int n = (int) s.size();
    int m = (int) c.size();
    string res = s;
    vector dp(2, vector(m + 1, vector<int>(n)));
    for (int z = 0; z < 2; z++) {
        vector<int> pref(n + 1);
        for (int i = 0; i < n; i++) {
            pref[i + 1] = pref[i] + (s[i] == '_');
        }
        vector<vector<int>> sum(m + 1, vector<int>(n + 1));
        for (int i = 0; i < m; i++) {
            int lst = -1;
            for (int j = 0; j + c[i] <= n; j++) {
                sum[i + 1][j + c[i]] = sum[i + 1][j + c[i] - 1];
                if (j > 0 && s[j - 1] == 'X') {
                    if (i == 0) {
                        for (int k = j + c[i] + 1; k <= n; k++) {
                            sum[1][k] = sum[1][k - 1];
                        }
                        break;
                    }
                    lst = j - 1;
                    continue;
                }
                if (j + c[i] < n && s[j + c[i]] == 'X') {
                    continue;
                }
                if (pref[j] != pref[j + c[i]]) {
                    continue;
                }
                if (i == 0 || sum[i][max(0, lst)] != sum[i][max(0, j - 1)]) {
                    dp[z][i + 1][j + c[i] - 1] = 1;
                    sum[i + 1][j + c[i]]++;
                }
            }
        }
        if (s[0] != 'X') {
            dp[z][0][0] = 1;
        }
        for (int i = 0; i <= m; i++) {
            for (int j = 1; j < n; j++) {
                if (dp[z][i][j - 1] && s[j] != 'X') {
                    dp[z][i][j] = 1;
                }
            }
        }
        reverse(s.begin(), s.end());
        reverse(c.begin(), c.end());
    }
    reverse(dp[1].begin(), dp[1].end());
    for (int i = 0; i <= m; i++) {
        reverse(dp[1][i].begin(), dp[1][i].end());
    }
    vector<int> pref(n + 1);
    for (int i = 0; i < n; i++) {
        pref[i + 1] = pref[i] + (s[i] == '_');
    }
    vector<int> sum(n + 1);
    for (int i = 0; i < m; i++) {
        for (int j = 0; j + c[i] <= n; j++) {
            if (j > 0 && s[j - 1] == 'X') {
                continue;
            }
            if (j + c[i] < n && s[j + c[i]] == 'X') {
                continue;
            }
            if (pref[j] != pref[j + c[i]]) {
                continue;
            }
            if (j >= 2 && !dp[0][i][j - 2]) {
                continue;
            }
            if (j < 2 && i != 0) {
                continue;
            }
            if (j + c[i] + 1 < n && !dp[1][i + 1][j + c[i] + 1]) {
                continue;
            }
            if (j + c[i] + 1 >= n && i != m - 1) {
                continue;
            }
            sum[j]++;
            sum[j + c[i]]--;
        }
    }
    for (int i = 0; i < n; i++) {
        sum[i + 1] += sum[i];
        if (res[i] != '.') {
            continue;
        }
        if (sum[i] == 0) {
            res[i] = '_';
            continue;
        }
        res[i] = 'X';
        if (i == 0) {
            if (n > 1 && dp[1][0][1]) {
                res[i] = '?';
            }
            continue;
        } else if (i == n - 1) {
            if (n > 1 && dp[0][m][n - 2]) {
                res[i] = '?';
            }
            break;
        }
        for (int j = 0; j <= m; j++) {
            if (dp[0][j][i - 1] && dp[1][j][i + 1]) {
                res[i] = '?';
            }
        }
    }
    return res;
}

#ifdef tabr
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    debug(solve_puzzle("..........", {3, 4}));
    debug(solve_puzzle("........", {3, 4}));
    debug(solve_puzzle("..._._....", {3}));
    debug(solve_puzzle(".X........", {3}));
    debug(solve_puzzle("....X..X...", {3, 3}));
    debug(solve_puzzle("..X_.._X...", {1, 2, 1}));
    debug(solve_puzzle(".._.X_.._.._X.", {2, 2, 2}));
    debug(solve_puzzle("..X_.._X....", {1, 2, 2}));
    debug(solve_puzzle(".X.._.......", {1, 2, 3}));
    return 0;
}
#endif

• 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