Submission #1030836

#	Time	Username	Problem	Language	Result	Execution time	Memory
1030836		c2zi6	Paint By Numbers (IOI16_paint)	C++14	80 / 100	2031 ms	1900 KiB

paint

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#include "paint.h"

bool solve(string s, VI c) {
    int n = s.size();
    int k = c.size();
    VI pref[3];
    pref[0] = pref[1] = pref[2] = VI(n+1);
    rep(i, n) {
        if (s[i] == '_') pref[0][i+1]++;
        else if (s[i] == 'X') pref[1][i+1]++;
        else if (s[i] == '.') pref[2][i+1]++;
        pref[0][i+1] += pref[0][i];
        pref[1][i+1] += pref[1][i];
        pref[2][i+1] += pref[2][i];
    }
    auto count = [&](int l, int r, string s) {
        int ret = 0;
        for (char ch : s) if (ch == '_') ret += pref[0][r+1] - pref[0][l];
        else if (ch == 'X') ret += pref[1][r+1] - pref[1][l];
        else if (ch == '.') ret += pref[2][r+1] - pref[2][l];
        return ret;
    };
    VVI dp(n+1, VI(k+1));
    dp[0][0] = true;
    replr(i, 1, n) {
        if (s[i-1] == 'X') break;
        dp[i][0] = true;
    }
    replr(i, 1, n) replr(j, 1, k) {
        if (s[i-1] != 'X') dp[i][j] |= dp[i-1][j];
        int sz = c[j-1];
        if (i-sz < 0 || count(i-sz, i-1, "_")) continue;
        if (i-sz == 0) dp[i][j] |= dp[0][j-1];
        else if (s[i-sz-1] != 'X') dp[i][j] |= dp[i-sz-1][j-1];
    }
    return dp[n][k];
}

string solve_puzzle(string s, VI c) {
    int n = s.size();
    int k = c.size();
    string ans(n, '?');
    rep(i, n) {
        if (s[i] != '.') ans[i] = s[i];
        else {
            s[i] = 'X';
            bool a = solve(s, c);
            s[i] = '_';
            bool b = solve(s, c);
            s[i] = '.';
            if (a && !b) ans[i] = 'X';
            else if (!a && b) ans[i] = '_';
        }
    }
    return ans;
}

Compilation message (stderr)

paint.cpp: In function 'std::string solve_puzzle(std::string, VI)':
paint.cpp:72:9: warning: unused variable 'k' [-Wunused-variable]
   72 |     int k = c.size();
      |         ^

• 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