Submission #290365

#	Time	Username	Problem	Language	Result	Execution time	Memory
290365		shayan_p	Paint By Numbers (IOI16_paint)	C++17	100 / 100	748 ms	199732 KiB

paint

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

#define F first
#define S second
#define PB push_back
#define sz(s) (int(s.size()))
#define bit(n, k) (((n)>>(k)) & 1)
#define any STRANGE

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;

const int maxn = 2e5 + 10, maxk = 110, mod = 1e9 + 7, inf = 1e9 + 10;

bool dp[2][maxk][maxn], slf[2][maxk][maxn];
int sm[maxn];

bool any(int l, int r){
    return sm[r] - sm[l-1] > 0;
}
void solve(string &s, vector<int> &c, bool dp[maxk][maxn], bool slf[maxk][maxn]){
    for(int i = 1; i <= sz(s); i++){
	sm[i] = sm[i-1] + (s[i-1] == '_');
    }
    dp[0][0] = 1;
    for(int i = 0; i <= sz(c); i++){
	for(int j = 1; j <= sz(s); j++){
	    dp[i][j] = 0;
	    slf[i][j] = 0;
	    if(s[j-1] != 'X')
		dp[i][j]|= dp[i][j-1];
	    if(i > 0){
		if(j > c[i-1])
		    slf[i][j]|= !any(j-c[i-1]+1, j) && s[j-1-c[i-1]] != 'X' && dp[i-1][j-c[i-1]-1];
		if(j == c[i-1])
		    slf[i][j]|= !any(1, j) && i == 1;
		dp[i][j]|= slf[i][j];
	    }
	}
    }
}

bool part[maxk][maxn], part2[maxk][maxn];
int partsm[maxk][maxn];

string solve_puzzle(string s, vector<int> c){ 
    solve(s, c, dp[0], slf[0]);
    reverse(s.begin(), s.end());
    reverse(c.begin(), c.end());
    solve(s, c, dp[1], slf[1]);
    reverse(s.begin(), s.end());
    reverse(c.begin(), c.end());
    
    for(int i = 1; i <= sz(s); i++){
	if(s[i-1] == 'X')
	    continue;
	for(int j = 0; j <= sz(c); j++)
	    part[j][i] = dp[0][j][i-1] && dp[1][sz(c)-j][sz(s)-i];
    }

    part2[sz(c)][sz(s) + 1] = slf[0][sz(c)][sz(s)];
    for(int i = 1; i <= sz(s); i++){
	if(s[i-1] == 'X')
	    continue;
	for(int j = 0; j <= sz(c); j++)
	    part2[j][i] = slf[0][j][i-1] && dp[1][sz(c)-j][sz(s)-i];
    }

    for(int i = 0; i <= sz(c); i++){
	partsm[i][0] = part2[i][0];
	for(int j = 1; j <= sz(s) + 1; j++)
	    partsm[i][j] = partsm[i][j-1] + part2[i][j];
    }
    
    string ans = s;
    for(int i = 0; i < sz(s); i++){
	if(s[i] == '.'){
	    bool A = 0, B = 0;
	    for(int j = 0; j < sz(c); j++){
		int l = i + 1, r = min(i + 1 + c[j], sz(s) + 1);
		A|= l <= r && (partsm[j+1][r] - partsm[j+1][l]);
	    }
	    for(int j = 0; j <= sz(c); j++){
		B|= part[j][i+1];
	    }
	    if(A && B)
		ans[i] = '?';
	    else if(A)
		ans[i] = 'X';
	    else if(B)
		ans[i] = '_';
	    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