Submission #581218

#	Time	Username	Problem	Language	Result	Execution time	Memory
581218		SlavicG	Paint By Numbers (IOI16_paint)	C++17	80 / 100	2092 ms	792 KiB

paint

#include "paint.h"
#include "bits/stdc++.h"

#define sz(a) (int)a.size()
#define pb push_back
#define all(a) a.begin(),a.end()
using ll = long long;
using namespace std;

bool ok(string s, vector<int> c) {
    s += '_';
    int n = s.size(), k = c.size();
    vector<vector<vector<int>>> dp(2, vector<vector<int>>(k + 1, vector<int>(n + 1, 0)));
    dp[0][0][0] = 1;
    c.pb(0);
    for(int i = 1; i <= n; ++i) {
        int f = (i % 2);
        for(int j = 0; j <= k; ++j) {
            for(int cur = 0; cur <= c[j]; ++cur) {
                dp[f][j][cur] = 0;
            }
        }

        for(int j = 0; j <= k; ++j) {
            for(int cur = 0; cur <= c[j]; ++cur) {
                char x = s[i - 1];
                if(x == 'X' || x == '.') {
                    if(cur >= 1) {
                        dp[f][j][cur] |= dp[!f][j][cur - 1];
                    }
                }
                if(x == '_' || x == '.') {
                    if(cur == 0) {
                        if(j) dp[f][j][cur] |= dp[!f][j - 1][c[j - 1]];
                        dp[f][j][cur] |= dp[!f][j][cur];
                    }
                }
            }
        }
    }
    return dp[n % 2][k][0];
}

string solve_puzzle(string s, vector<int> c) {
    string ans = "";
    int n = sz(s);

    for(int i = 0; i < n; ++i) {
        if(s[i] == 'X') {
            ans += 'X';
        } else if(s[i] == '_') {
            ans += '_';
        } else {
            s[i] = 'X';
            bool ok1 = ok(s, c);
            s[i] = '_';
            bool ok2 = ok(s, c);
            assert(ok1 || ok2);
            if(ok1 && ok2) {
                ans += '?';
            } else if(ok1) {
                ans += 'X';
            } else {
                ans += '_';
            }
            s[i] = '.';
        }
    }
    return ans;
}

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