Submission #567972

#	Time	Username	Problem	Language	Result	Execution time	Memory
567972		ngpin04	Paint By Numbers (IOI16_paint)	C++17	90 / 100	2085 ms	49428 KiB

paint

#include "paint.h"
#include <bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define TASK ""
#define bit(x) (1LL << (x))
#define getbit(x, i) (((x) >> (i)) & 1)
#define ALL(x) (x).begin(), (x).end() 
using namespace std;
template <typename T1, typename T2> bool mini(T1 &a, T2 b) {
    if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maxi(T1 &a, T2 b) {
    if (a < b) {a = b; return true;} return false;
}
mt19937_64 rd(chrono::steady_clock::now().time_since_epoch().count());

int rand(int l, int r) {
    return l + rd() % (r - l + 1);
}
const int N = 2e5 + 5; 
const int K = 105;
const int oo = 1e9;
const long long ooo = 1e18;
const int mod = 1e9 + 7; // 998244353;
const long double pi = acos(-1);

int cnt[N][2];
int ans[N][2];
int a[N];
int b[N];
int n,k;

bool pre[N][K];
bool suf[N][K];

int fix(char c) {
    if (c == '.')
        return -1;
    if (c == '_')
        return 0;
    return 1;
}

int check(int l, int r, int v) {
    return (cnt[r][v] - cnt[l - 1][v]) > 0;
}

void solve() {

    for (int i = 1; i <= n; i++) {
        if (a[i] != -1)
            cnt[i][a[i]]++;
        for (int j = 0; j < 2; j++)
            cnt[i][j] += cnt[i - 1][j];
    }

    for (int i = 0; i <= n; i++) {
        if (a[i] == 1)
            break;
        pre[i][0] = 1;
    }

    for (int j = 1; j <= k; j++)
    for (int i = b[j]; i <= n; i++) {
        if (a[i] != 1)
            pre[i][j] |= pre[i - 1][j];
        if (!check(i - b[j] + 1, i, 0)) {
            int it = i - b[j];
            if (a[it] != 1)
                pre[i][j] |= pre[max(0, it - 1)][j - 1];
        }
    }

    for (int i = n + 1; i >= 1; i--) {
        if (a[i] == 1)
            break;
        suf[i][k + 1] = 1;
    }

    for (int j = k; j >= 1; j--)
    for (int i = n - b[j] + 1; i >= 1; i--) {
        if (a[i] != 1)
            suf[i][j] |= suf[i + 1][j];
        if (!check(i, i + b[j] - 1, 0)) {
            int it = i + b[j];
            if (a[it] != 1)
                suf[i][j] |= suf[min(n + 1, it + 1)][j + 1];
        }
    }

    for (int i = 1; i <= n; i++) if (a[i] != 1) 
    for (int j = 0; j <= k; j++)
        if (pre[i - 1][j] && suf[i + 1][j + 1])
            ans[i][0] = true;

    for (int j = 1; j <= k; j++) 
    for (int l = 1, r = b[j]; r <= n; l++, r++) if (!check(l, r, 0)) {
        if (j > 1 && a[l - 1] == 1)
            continue;
        if (j < k && a[r + 1] == 1)
            continue;
        int u = (l - 1) - (j > 1);
        int v = (r + 1) + (j < k);
        if (u < 0 || v > n + 1)
            continue;
        if (pre[u][j - 1] && suf[v][j + 1]) {
            ans[l][1]++;
            ans[r + 1][1]--;
            cerr << l << " " << r << " " << j << "\n";
        }
    }

    for (int i = 1; i <= n; i++)
        ans[i][1] += ans[i - 1][1];
}

string solve_puzzle(string s, vector<int> c) {
    n = s.size();
    k = c.size();
    for (int i = 1; i <= n; i++)
        a[i] = fix(s[i - 1]);

    for (int i = 1; i <= k; i++)
        b[i] = c[i - 1];

    solve();

    string res;
    for (int i = 1; i <= n; i++) {
        assert(ans[i][0] || ans[i][1]);
        if (ans[i][0] && ans[i][1])
            res += '?';
        else if (ans[i][0])
            res += '_';
        else
            res += 'X';
    }
    return res;
}

//#include "grader.cpp"

• 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: 0 / 10