Submission #936194

#	Time	Username	Problem	Language	Result	Execution time	Memory
936194		GrindMachine	Paint By Numbers (IOI16_paint)	C++17	100 / 100	199 ms	85392 KiB

paint

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*



*/

const int MOD = 1e9 + 7;
const int N = 1e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

#include "paint.h"

std::string solve_puzzle(std::string s, std::vector<int> a) {
    int n = sz(s);
    s = "$" + s;
    int m = sz(a);
    a.insert(a.begin(),0);

    vector<int> p(n+5);
    rep1(i,n) p[i] = p[i-1]+(s[i] == '_');

    bool dp1[n+5][m+5][2], dp2[n+5][m+5][2];
    memset(dp1,0,sizeof dp1);
    memset(dp2,0,sizeof dp2);
    dp1[0][0][0] = 1;

    rep1(i,n){
        rep(j,m+1){
            if(s[i] != 'X'){
                dp1[i][j][0] = dp1[i-1][j][0]|dp1[i-1][j][1];
            }
            if(s[i] != '_'){
                if(j and i-a[j] >= 0 and p[i]-p[i-a[j]] == 0){
                    dp1[i][j][1] = dp1[i-a[j]][j-1][0];
                }
            }
        }
    }

    dp2[n+1][m+1][0] = 1;

    rev(i,n,1){
        rep1(j,m+1){
            if(s[i] != 'X'){
                dp2[i][j][0] = dp2[i+1][j][0]|dp2[i+1][j][1];
            }
            if(s[i] != '_'){
                if(j <= m and i+a[j] <= n+1 and p[i+a[j]-1]-p[i-1] == 0){
                    dp2[i][j][1] = dp2[i+a[j]][j+1][0];
                }
            }
        }
    }

    vector<bool> white(n+5), black(n+5);

    rep1(i,n){
        if(s[i] == 'X') conts;
        rep(j,m+1){
            if((dp1[i-1][j][0]|dp1[i-1][j][1]) and (dp2[i+1][j+1][0]|dp2[i+1][j+1][1])){
                white[i] = 1;
            }
        }
    }

    vector<int> diff(n+5);

    rep(i,n+1){
        rep(j,m){
            int len = a[j+1];
            if(i+len+1 <= n+1){
                if(dp1[i][j][0] and dp2[i+len+1][j+2][0]){
                    int white_cnt = p[i+len]-p[i];
                    if(white_cnt == 0){
                        diff[i+1]++;
                        diff[i+len+1]--;
                    }
                }
            }
        }
    }

    rep1(i,n){
        diff[i] += diff[i-1];
        black[i] = (diff[i] > 0);
    }

    string ans = "";

    rep1(i,n){
        if(s[i] != '.'){
            ans.pb(s[i]);
            conts;
        }

        bool w = white[i], b = black[i];
        if(w+b == 2){
            ans.pb('?');
        }
        else if(w){
            ans.pb('_');
        }
        else if(b){
            ans.pb('X');
        }
        else{
            assert(0);
        }
    }

    return ans;
}

• 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: 10 / 10