Ruudukko

#include <bits/stdc++.h>

using namespace std;

const int N = 501;

int n;
string m[N];
string r = "";
string cr = "";

void haku(int x, int y)
{
    cr.push_back(m[x][y]);
    if(x==n && y == n)
    {
        if(r == "") r = cr;
        else r = min(r, cr);
    }
    else if(x<n && y==n) haku(x+1,y);
    else if(y<n && x==n) haku(x,y+1);
    else
    {
        if(m[x][y+1] <= m[x+1][y]) haku(x,y+1);
        if(m[x][y+1] >= m[x+1][y]) haku(x+1,y);
    }
    cr.pop_back();
}

int main()
{
    cin>>n;
    string s;
    for(int i=0;i<n;i++)
    {
        cin>>s;
        m[i] = s;
    }
    n--;
    haku(0,0);
    cout<<r;
}

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: 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