Submission #287031

#	Time	Username	Problem	Language	Result	Execution time	Memory
287031		Shafin666	Paint By Numbers (IOI16_paint)	C++14	59 / 100	1 ms	512 KiB

paint

#include <bits/stdc++.h>
#define pb push_back
#define pii pair<ll, ll>
#define nyan "(=^･ω･^=)"
#define read_input         freopen("in.txt","r", stdin)
#define print_output       freopen("out.txt","w", stdout)
typedef long long ll;
typedef long double ld;
using namespace std;

const int maxn = 2e5+10, maxk = 103;
int n, k;

int dp1[maxn][maxk], dp2[maxn][maxk];
int dash[maxn], crs[maxn]; 
int lft[maxn], rgt[maxn], aux[maxn];
string str;

int x[maxn], y[maxn];

bool okx(int l, int r) {
    if(l >= 2 && str[l-2] == 'X') return 0;
    if(r < n && str[r] == 'X') return 0;
    return (dash[r] - dash[l-1] == 0);
}

std::string solve_puzzle(std::string s, std::vector<int> c) {
    n = s.length(); str = s;
    k = c.size();

    for(int i = 1; i <= n; i++) dash[i] = dash[i-1] + (s[i-1] == '_');
    for(int i = 1; i <= n; i++) crs[i] = crs[i-1] + (s[i-1] == 'X');

    aux[0] = 1; dp1[0][0] = 1;
    for(int i = 1; i <= n && str[i-1] != 'X'; i++) aux[i] = 1, dp1[i][0] = 1;


    for(int j = 1, pos = 0; j <= k; j++) {
        for(int i = 1; i <= n; i++) {
            if(i < c[j-1]) continue;

            if(j > 1) dp1[i][j] = aux[i - c[j-1] - 1] & okx(i - c[j-1] + 1, i);
            else dp1[i][j] = aux[i - c[j-1]] & okx(i - c[j-1] + 1, i);

            dp1[i][j] = dp1[i][j] & (crs[max(i - c[j-1] - 1, 0)] == crs[pos]);
        }

        aux[0] = 0;
        for(int i = 1; i <= n; i++) {
            aux[i] = max(aux[i-1], dp1[i][j]);
            if(dp1[i][j]) pos = i;
        }
    }

    reverse(str.begin(), str.end());
    reverse(c.begin(), c.end());


    for(int i = 1; i <= n; i++) dash[i] = dash[i-1] + (str[i-1] == '_');
    for(int i = 1; i <= n; i++) crs[i] = crs[i-1] + (str[i-1] == 'X');

    aux[0] = 1; dp2[0][0] = 1;
    for(int i = 1; i <= n && str[i-1] != 'X'; i++) aux[i] = 1, dp2[i][0] = 1;


    for(int j = 1, pos = 0; j <= k; j++) {
        for(int i = 1; i <= n; i++) {
            if(i < c[j-1]) continue;
            
            if(j > 1) dp2[i][j] = aux[i - c[j-1] - 1] & okx(i - c[j-1] + 1, i);
            else dp2[i][j] = aux[i - c[j-1]] & okx(i - c[j-1] + 1, i);

            dp2[i][j] = dp2[i][j] & (crs[max(i - c[j-1] - 1, 0)] == crs[pos]);
        }

        aux[0] = 0;
        for(int i = 1; i <= n; i++) {
            aux[i] = max(aux[i-1], dp2[i][j]);
            if(dp2[i][j]) pos = i;
        }
    }

    for(int j = 1; j <= k; j++) {
        for(int i = 1; i <= n; i++)
            dp2[i][j] = max(dp2[i-1][j], dp2[i][j]);
    }

    for(int j = 0; j <= k; j++) {
        for(int i = 1; 2*i <= n; i++) swap(dp2[i][j], dp2[n-i+1][j]);
        dp2[n+1][0] = 1;
    }

    reverse(c.begin(), c.end());

    for(int i = 1; i <= n; i++) {
        for(int j = 1; j <= k; j++) {
            if(i == n) {
                if(dp1[i][j] & dp2[i+1][k-j]) x[i+1]--, x[i - c[j-1] + 1]++;
            }
            else {
                if(dp1[i][j] && dp2[i+2][k-j]) x[i+1]--, x[i - c[j-1] + 1]++;
            }
        }
    }

    for(int j = 1; j <= k; j++) {
        for(int i = 1; i <= n; i++)
            dp1[i][j] = max(dp1[i-1][j], dp1[i][j]);
    }

    for(int i = 1; i <= n; i++) {
        for(int j = 0; j <= k; j++) {
            y[i] = max(y[i], dp1[i-1][j] & dp2[i+1][k-j]);
        }
    }

    
    for(int i = 1; i <= n; i++) x[i] += x[i-1];
    for(int i = 1; i <= n; i++) x[i] = (x[i] > 0);

    string res = "";

    for(int i = 1; i <= n; i++) {
        if(s[i-1] == 'X') res += "X";
        else if(s[i-1] == '_') res += "_";
        else if(x[i] && y[i]) res += "?";
        else if(y[i]) res += "_";
        else res += "X";
    }
    return res;
}

• 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