Submission #967005

#	Time	Username	Problem	Language	Result	Execution time	Memory
967005		Boomyday	Paint By Numbers (IOI16_paint)	C++17	100 / 100	306 ms	33116 KiB

paint

#include "paint.h"

#include <bits/stdc++.h>
using namespace std;

using ll = long long;




std::string solve_puzzle(std::string s, std::vector<int> c) {
    int n = s.size(), k = c.size();
    vector<int> prf0 = {0}; // 0
    vector<int> prf1 = {0}; // 1
    vector<int> rup1(n+1,0);
    vector<int> ans0(n+1,0);

    for(int i=0;i<n;++i){
        prf0.push_back(prf0.back() + (s[i]=='_'));
        prf1.push_back(prf1.back() + (s[i]=='X'));
    }

    vector<vector<bool>> dp(n+1,vector<bool>(k+1,0));

    // base cases
    dp[n][k] = 1;
    for(int j=0;j<k;++j) dp[n][j] = 0;
    for(int i=0;i<n;++i){
        if (prf1[n]-prf1[i]==0) dp[i][k] = 1;
        else dp[i][k] = 0;
    }



    for(int i=n-1;i>=0;--i){
        for(int j=k-1;j>=0;--j){
            if (s[i] != '_') { // 1
                if (i + c[j] <= n){
                    if (prf0[i+c[j]]-prf0[i] == 0){
                        if (i+c[j] != n){
                            if (s[i+c[j]] != 'X'){
                                dp[i][j] = (dp[i][j] || dp[i+c[j]+1][j+1]);
                            }
                        }
                        else dp[i][j] = (dp[i][j] || dp[i+c[j]][j+1]);
                    }
                }

            }
            if (s[i] != 'X') { //0
                dp[i][j] = (dp[i][j] || dp[i+1][j]);

            }
        }
    }

    //cout << "dp " << dp[0][0] << endl;

    // answer extraction

    vector<vector<bool>> dp2(n+1,vector<bool>(k+1,0));
    dp2[0][0] = 1;

    for(int i=0;i<n;++i){
        for(int j=0;j<=k;++j){
            if (!dp2[i][j] || !dp[i][j]) continue;



            if (s[i] != '_' && j != k) { // 1
                if (i + c[j] <= n){
                    if (prf0[i+c[j]]-prf0[i] == 0){
                        if (i+c[j] != n){
                            if (s[i+c[j]] != 'X'){
                                if (dp[i+c[j]+1][j+1]){
                                    dp2[i+c[j]+1][j+1] = 1;
                                    rup1[i]++; rup1[i+c[j]]--; ans0[i+c[j]]=1;
                                }
                            }
                        }
                        else{
                            if (dp[i+c[j]][j+1]){
                                dp2[i+c[j]][j+1] = 1;
                                rup1[i]++; rup1[i+c[j]]--;
                            }
                        }
                    }
                }

            }
            if (s[i] != 'X') { //0
                if (dp[i+1][j]){
                    dp2[i+1][j] = 1;
                    ans0[i] = 1;
                }

            }




        }
    }

    // complete the rupq

    for(int i=1;i<n;++i){
        rup1[i] += rup1[i-1];
    }

    string ans;
    for(int i=0;i<n;++i){
        //cout << "rup1 " << rup1[i] << " ans0 " << ans0[i] << endl;
        if (rup1[i] > 0 && ans0[i] > 0){
            ans.push_back('?');
        }
        else if (rup1[i] > 0 ) ans.push_back('X');
        else ans.push_back('_');
    }
    return ans;


}


/*
#include <vector>
#include <string>
#include <cstdio>
#include <cassert>

const int S_MAX_LEN = 200 * 1000;
char buf[S_MAX_LEN + 1];

int main() {
    assert(1 == scanf("%s", buf));
    std::string s = buf;
    int c_len;
    assert(1 == scanf("%d", &c_len));
    std::vector<int> c(c_len);
    for (int i = 0; i < c_len; i++) {
        assert(1 == scanf("%d", &c[i]));
    }
    std::string ans = solve_puzzle(s, c);


    printf("%s\n", ans.data());
    return 0;
}




*/

• 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