Submission #71354

#	Time	Username	Problem	Language	Result	Execution time	Memory
71354		hamzqq9	Paint By Numbers (IOI16_paint)	C++14	100 / 100	683 ms	211796 KiB

paint

#include "paint.h"
#include<bits/stdc++.h>
#define st first
#define nd second
#define pb push_back
#define ppb pop_back
#define umax(x,y) x=max(x,y)
#define umin(x,y) x=min(x,y)
#define ll long long
#define ii pair<int,int>
#define iii pair<int,ii>
#define sz(x) ((int) x.size())
#define orta ((bas+son)>>1)
#define all(x) x.begin(),x.end()
#define dbgs(x) cerr<<(#x)<<" --> "<<(x)<<" "
#define dbg(x) cerr<<(#x)<<" --> "<<(x)<<endl;getchar()
#define pw(x) (1<<(x))
#define inf 2000000000
#define MOD 1000000007
#define N 200005
#define MAX 10000006
#define K 105
#define LOG 30
#define KOK 200
using namespace std;

int n,k;
bool dp[2][K][N],_[N];
int predp[2][K][N],ok[2][N],px[N],nr[2][N],pre_[2][N];
vector<int> c;
string s;

void find_pos() {

	// try empty

	for(int i=1;i<=n;i++) {

		if(s[i]=='.') {

			bool okey=false;

			for(int j=0;j<=k;j++) {

				if(predp[0][j][i-1]-(nr[0][i-1]-1<0?0:predp[0][j][nr[0][i-1]-1])>0 && predp[1][k-j][n-i]-(nr[1][n-i]-1<0?0:predp[1][k-j][nr[1][n-i]-1])>0) {
					
					okey=true;

				}
			
			}

			if(okey) _[i]=1;

		}

	}

	// try X

	for(int i=n;i>=1;i--) {

		if(dp[0][k][i]) ok[0][i]++,ok[0][i+1]--;

		if(s[i]=='X') break ;

	}

	for(int i=k;i>=1;i--) {

		for(int j=1;j<=n;j++) {

			ok[0][j]+=ok[0][j-1];

			if(ok[0][j] && dp[0][i][j] && s[j+1]!='X') {

				px[j-c[i]+1]++;
				px[j+1]--;
				ok[1][j-c[i]]--;
				ok[1][nr[0][max(0,j-c[i]-1)]]++;

			}

		}

		for(int j=0;j<=n;j++) {

			ok[0][j]=ok[1][j];

			ok[1][j]=0;

		}

	}

	px[0]=0;

	for(int i=1;i<=n;i++) {

		px[i]+=px[i-1];

		if(s[i]!='.') continue ;

		if(px[i] && _[i]) {

			s[i]='?';

		}
		else if(px[i]) s[i]='X';
		else s[i]='_';

	}

}

void solve(int w) {

	for(int i=0;i<=n && !nr[w][i];i++) dp[w][0][i]=1;
		
	predp[w][0][0]=dp[w][0][0];

	for(int i=1;i<=n;i++) predp[w][0][i]=predp[w][0][i-1]+dp[w][0][i];

	for(int i=1;i<=k;i++) {

		for(int j=1;j<=n;j++) {

			if(c[i]>j) continue ;

			if(pre_[w][j]-pre_[w][j-c[i]]) continue ;

			if(s[j-c[i]]=='X') continue ;

			if(j-c[i]-1>=0) {

				dp[w][i][j]=(predp[w][i-1][j-c[i]-1]-(nr[w][j-c[i]-1]-1<0?0:predp[w][i-1][nr[w][j-c[i]-1]-1])>0);

			}
			else if(i==1) dp[w][i][j]=1;

		}

		predp[w][i][0]=dp[w][i][0];

		for(int j=1;j<=n;j++) predp[w][i][j]=predp[w][i][j-1]+dp[w][i][j];

	}

	/*for(int i=1;i<=k;i++) {

		for(int j=0;j<=n;j++) {

			printf("%d %d %d %d\n",w,i,j,dp[w][i][j]);

		}

	}*/

}

void fpre(int w) {

	for(int i=1;i<=n;i++) {

		pre_[w][i]=pre_[w][i-1]+(s[i]=='_');

	}

}

void fnears(int w) {

	int near=0;

	for(int i=1;i<=n;i++) {

		if(s[i]=='X') near=i;

		nr[w][i]=near;

	}

}

void pre_cal() {

	n=sz(s)-2;
	k=sz(c)-2;

	fnears(0);
	fpre(0);

	reverse(all(s));
	reverse(all(c));

	fnears(1);
	fpre(1);	

	reverse(all(s));
	reverse(all(c));

}

void solve_dp() {

	solve(0);

	reverse(all(s));
	reverse(all(c));

	solve(1);

	reverse(all(s));
	reverse(all(c));

}

std::string solve_puzzle(std::string s, std::vector<int> c) {
    
	::s=" "+s+" ";
	::c.pb(0);

	for(int i=0;i<sz(c);i++) ::c.pb(c[i]);

	::c.pb(0);

	pre_cal();
	
	solve_dp();

	find_pos();

	string result;

	for(int i=1;i<=n;i++) result.pb(::s[i]);

	return result;

}

• 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