Ruudukko

#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int s = 0;

struct rt {
	vector<char> str;
	int x, y;
	int i;
	rt(char c): x(0), y(0), i(1) {
		str = vector<char>(s + 1);
		str[0] = c;
	}
	rt(const rt& o): x(o.x), y(o.y), i(o.i) {
		str = vector<char>(s + 1);
		for (int j = 0; j < s; j++) {
			str[j] = o.str[j];
		}
	}
};

bool cmp(rt a, rt b) {
	for (int i = 0; i < s; i++) {
		if (a.str[i] < b.str[i]) return true;
		if (a.str[i] > b.str[i]) return false;
	}
	return false;
}

int main() {
	cin.sync_with_stdio(false);
	int n;
	cin >> n;
	vector<vector<char> > r(n);
	for (int i = 0; i < n; i++) {
		r[i] = vector<char>(n);
		for (int j = 0; j < n; j++) {
			cin >> r[i][j];
		}
	}
	// siirtomäärä
	s = n * n - 2 * n + 1;
	vector<rt> t(n * n, rt(0x7F));
	int m = 1;
	t[0] = rt(r[0][0]);
	for (int i = 0; i < s; i++) {
		int u = m;
		for (int j = 0; j < u; j++) {
			if (t[j].x == n - 1)
				t[j].str[t[j].i++] = r[t[j].x][++t[j].y];
			else if (t[j].y == n - 1)
				t[j].str[t[j].i++] = r[++t[j].x][t[j].y];
			else {
				char a = r[t[j].x + 1][t[j].y];
				char b = r[t[j].x][t[j].y + 1];
				if (a < b)
					t[j].str[t[j].i++] = r[++t[j].x][t[j].y];
				else if (b < a)
					t[j].str[t[j].i++] = r[t[j].x][++t[j].y];
				else {
					rt o(t[j]);
					t[j].str[t[j].i++] = r[++t[j].x][t[j].y];
					o.str[o.i++] = r[o.x][++o.y];
					t[m++] = o;
				}
			} 
		}
	}
	sort(t.begin(), t.end(), cmp);
	for (int i = 0; i <= s; i++) {
		cout << t[0].str[i];
	}
	cout << endl;
}

Test 1

Group: 1

Verdict: RUNTIME ERROR

Test 2

Group: 1

Verdict: RUNTIME ERROR

Test 3

Group: 1

Verdict: WRONG ANSWER

Test 4

Group: 1

Verdict: WRONG ANSWER

Test 5

Group: 1

Verdict: WRONG ANSWER

Test 6

Group: 2

Verdict: RUNTIME ERROR

Test 7

Group: 2

Verdict: RUNTIME ERROR

Test 8

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 3

Verdict: RUNTIME ERROR

Test 15

Group: 3

Verdict: TIME LIMIT EXCEEDED