Ruudukko

input/code.cpp: In function 'void askel()':
input/code.cpp:12:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (ll j=0; j<xy.size(); j++) s += t[xy[j]];
                   ^

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
ll n,x=0,y=0;
vector<char> t;
vector<ll> xy;
string pienin;
void askel() {
  xy.push_back(x+n*y);
  if (x==n-1 && y==n-1) {
    string s;
    for (ll j=0; j<xy.size(); j++) s += t[xy[j]];
    if (s < pienin || pienin.length() == 0) pienin = s;
    return;
  }
  if (x>=n || y>=n) return;
  x++;
  askel();
  x--;
  xy.pop_back();
  y++;
  askel();
  y--;
  xy.pop_back();
}
int main() {
  cin >> n;
  for (ll i=0; i<n; i++) {
    string s;
    cin >> s;
    for (ll j=0; j<n; j++) t.push_back(s[j]);
  }
  askel();
  cout << pienin << "\n";
}

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: TIME LIMIT EXCEEDED

Test 7

Group: 2

Verdict: TIME LIMIT EXCEEDED

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: TIME LIMIT EXCEEDED

Test 15

Group: 3

Verdict: TIME LIMIT EXCEEDED