Ruudukko

input/code.cpp: In function 'std::vector<char> min_v(std::vector<char>, std::vector<char>)':
input/code.cpp:7:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 0; i < a.size(); i++){
                    ^

#include <iostream>
#include <vector>

using namespace std;

vector <char> min_v(vector<char> a, vector<char> b){
  for(int i = 0; i < a.size(); i++){
    if(a[i] > b[i])
      return b;
    else if(a[i] < b[i])
      return a;
  }
  return a;
}

int n;
char table[6250000];
vector<char> fcache[6250000];

vector <char> f(int x, int y){
  if(fcache[x*n + y].size() == 0){
    vector <char> result;
    result.push_back(table[x*n + y]);
    if(x == (n-1) and y == (n-1)){
      // Nothing to do here 
    }else if(x == (n-1)){
      for(char k : f(x, y+1))
        result.push_back(k);
    }else if(y == (n-1)){
      for(char k : f(x+1, y))
        result.push_back(k);
    }else{
      for(char k : min_v(f(x+1, y), f(x, y+1)))
        result.push_back(k);
    }
    fcache[x*n + y] = result;
  }
  return fcache[x*n + y];
}

int main(){

  cin >> n;
  for(int x = 0; x < n; x++){
    for(int y = 0; y < n; y++){
      char c;
      cin >> c;
      table[x*n + y] = c;
    }
  }
  for(char c : f(0, 0))
    cout << c;
  cout << 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: 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