Ruudukko

#include <iostream>
 
using namespace std;
 
char ruudukko[510][510];
string paras[510][510];
 
int n;
 
string rakenna(int x, int y)
{
	if(paras[x][y] != "")
		return paras[x][y];
 
	char a = ruudukko[x + 1][y];
	char b = ruudukko[x][y + 1];
 
	if(a == 0)
		a = 127;
 
	if(b == 0)
		b = 127;
 
	string l;
 
	if(a < b)
	{
		l = rakenna(x + 1, y);
	}
	else if(b < a)
	{
		l = rakenna(x, y + 1);
	}
	else if(a != 127)
	{
		string as, bs;
 
		as = rakenna(x + 1, y);
		bs = rakenna(x, y + 1);
 
		if(as < bs)
			l = as;
		else
			l = bs;
	}
 
	string ans;
	ans.push_back(ruudukko[x][y]);
	ans.append(l);
 
	return paras[x][y] = ans;
}
 
int main()
{
	ios_base::sync_with_stdio(false);
	cin.tie(0);
 
	
	cin >> n;
 
	for(int j = 0; j < n; j++)
	{
		for(int i = 0; i < n; i++)
		{
			cin >> ruudukko[i][j];
		}
	}
 
 
	cout << rakenna(0, 0) << endl;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED