Submission #513884

#	Time	Username	Problem	Language	Result	Execution time	Memory
513884		tabr	Paint By Numbers (IOI16_paint)	C++17	59 / 100	1 ms	308 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 k = (int) c.size();
    vector<vector<int>> a(2, vector<int>(k));
    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>> dp(k, vector<int>(n, n));
        for (int i = 0; i < k; i++) {
            int lst = -1;
            for (int j = 0; j + c[i] <= n; j++) {
                if (j > 0 && s[j - 1] == 'X') {
                    if (i == 0) {
                        break;
                    }
                    lst = j;
                    continue;
                }
                if (j + c[i] < n && s[j + c[i]] == 'X') {
                    continue;
                }
                if (pref[j] != pref[j + c[i]]) {
                    continue;
                }
                if (i == 0) {
                    dp[i][j] = -1;
                } else {
                    for (int l = 0; l + c[i - 1] < j; l++) {
                        if (dp[i - 1][l] < n && (lst == -1 || (l <= lst && lst < l + c[i - 1]))) {
                            dp[i][j] = l;
                            break;
                        }
                    }
                }
            }
        }
        int lst = -1;
        for (int i = n - 1; i >= 0; i--) {
            if (s[i] == 'X') {
                lst = i;
                break;
            }
        }
        int pos = -1;
        for (int i = 0; i < n; i++) {
            if (dp[k - 1][i] != n && (lst == -1 || lst < i + c[k - 1])) {
                pos = i;
                break;
            }
        }
        for (int i = k - 1; i >= 0; i--) {
            a[z][i] = pos;
            pos = dp[i][pos];
        }
        reverse(s.begin(), s.end());
        reverse(c.begin(), c.end());
    }
    reverse(a[1].begin(), a[1].end());
    for (int i = 0; i < k; i++) {
        a[1][i] = n - 1 - a[1][i];
    }
    for (int i = 0; i < k; i++) {
        for (int j = a[1][i] - c[i] + 1; j <= a[0][i] + c[i] - 1; j++) {
            s[j] = 'X';
        }
    }
    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 < k; 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 (a[0][i] <= j && j + c[i] - 1 <= a[1][i]) {
                sum[j]++;
                sum[j + c[i]]--;
            }
        }
    }
    for (int i = 0; i < n; i++) {
        sum[i + 1] += sum[i];
        if (s[i] == '.') {
            s[i] = (sum[i] > 0 ? '?' : '_');
        }
    }
    return s;
}

#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}));
    return 0;
}
#endif

• Subtask 1: 7 / 7
• Subtask 2: 3 / 3
• Subtask 3: 22 / 22
• Subtask 4: 27 / 27
• Subtask 5: 0 / 21
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10