Submission #619650

#	Time	Username	Problem	Language	Result	Execution time	Memory
619650		Bench0310	Paint By Numbers (IOI16_paint)	C++17	100 / 100	372 ms	160592 KiB

paint

#include <bits/stdc++.h>
#include "paint.h"

using namespace std;
typedef long long ll;

const int N=200000;
const int K=200;
bool one[N+1][K+1][2];
bool two[N+2][K+2][2];

string solve_puzzle(string s,vector<int> c)
{
    int n=s.size();
    int k=c.size();
    c.insert(c.begin(),0);
    s="$"+s;
    vector<int> wsum(n+1,0);
    for(int i=1;i<=n;i++) wsum[i]=wsum[i-1]+(s[i]=='_');
    auto ws=[&](int l,int r)->int{return (wsum[r]-wsum[l-1]);};
    one[0][0][1]=1;
    for(int i=1;i<=n;i++)
    {
        //extend
        for(int j=0;j<=k;j++) one[i][j][1]=((one[i-1][j][0]||one[i-1][j][1])&&(s[i]!='X'));
        //new block
        for(int j=1;j<=k;j++) if(i-c[j]>=0) one[i][j][0]=(one[i-c[j]][j-1][1]&&ws(i-c[j]+1,i)==0);
    }
    two[n+1][k+1][1]=1;
    for(int i=n;i>=1;i--)
    {
        //extend
        for(int j=1;j<=k+1;j++) two[i][j][1]=((two[i+1][j][0]||two[i+1][j][1])&&(s[i]!='X'));
        //new block
        for(int j=1;j<=k;j++) if(i+c[j]<=n+1) two[i][j][0]=(two[i+c[j]][j+1][1]&&ws(i,i+c[j]-1)==0);
    }
    vector<int> d(n+2,0);
    vector<bool> white(n+1,0);
    for(int i=1;i<=n;i++)
    {
        //white
        for(int j=0;j<=k;j++) if(one[i][j][1]&&two[i][j+1][1]) white[i]=1;
        //black
        for(int j=1;j<=k;j++)
        {
            if(one[i][j][0]&&two[i+1][j+1][1])
            {
                d[i-c[j]+1]++;
                d[i+1]--;
            }
        }
    }
    int black=0;
    string res(n,'?');
    for(int i=1;i<=n;i++)
    {
        black+=d[i];
        if(white[i]&&black) res[i-1]='?';
        else if(white[i]) res[i-1]='_';
        else if(black) res[i-1]='X';
    }
    return res;
}

• 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