#include <bits/stdc++.h>
#define ll long long
#define pll pair<ll,ll>
#define pb push_back
#define eb emplace_back
#define vl vector<ll>
#define fi first
#define se second
#define in insert
#define mpr make_pair
#define lg(x) __lg(x)
#define bpc(x) __builtin_popcount(x)
#define all(v) v.begin(), v.end()
#define endl "\n"
using namespace std;
const int mod = 998244353;
ll can[35][35], used[35][35];
char a[35][35];
//bool used[35][35];
vector<char> v(66, '#');
ll n, m;
ll rec(ll x, ll y){
if(x > n || y > m){return 0;}
if(v[x + y - 2] == a[x][y]){
if(v[x + y - 1] == '#'){return can[x][y];}
if(used[x][y] != -1){
return used[x][y];
}
ll ret = rec(x+1, y) + rec(x, y+1);
return used[x][y] = ret;
}
return 0;
}
void solve()
{
ll i, j, k;
cin>>n>>m;
for(i=1;i<=n;i++){
can[i][m] = 1;
for(j=1;j<=m;j++){
can[n][j] = 1;
cin>>a[i][j];
}
}
cin>>k;
for(i = n-1; i>0; i--){
for(j = m-1; j>0; j--){
can[i][j] = can[i+1][j] + can[i][j+1];
}
}
v[0] = a[1][1];
for(i=1;i<(n+m-1);i++){
for(j = 'a'; j <= 'z'; j++){
v[i] = char(j);
memset(used, -1, sizeof(used));
ll dk = rec(1, 1);
if(dk >= k){
///cout << i << ' ' << char(j) << ' ' << dk << endl;
break;
}
k -= dk;
}
if(k <= 0){
break;
}
}
string final = "";
for(i=0;i<(n+m-1);i++){
final += v[i];
}
cout << final << endl;
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
//precomp();
ll tst=1;
//cin>>tst;
while(tst--){
solve();
}
}
/*
ok.
*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Correct |
0 ms |
348 KB |
Output is correct |
6 |
Correct |
0 ms |
348 KB |
Output is correct |
7 |
Correct |
0 ms |
344 KB |
Output is correct |
8 |
Correct |
0 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
1 ms |
348 KB |
Output is correct |
11 |
Correct |
2 ms |
348 KB |
Output is correct |
12 |
Correct |
1 ms |
348 KB |
Output is correct |
13 |
Correct |
1 ms |
456 KB |
Output is correct |
14 |
Correct |
1 ms |
348 KB |
Output is correct |
15 |
Correct |
1 ms |
348 KB |
Output is correct |
16 |
Correct |
1 ms |
344 KB |
Output is correct |
17 |
Correct |
1 ms |
348 KB |
Output is correct |
18 |
Correct |
1 ms |
348 KB |
Output is correct |
19 |
Correct |
1 ms |
348 KB |
Output is correct |
20 |
Correct |
1 ms |
348 KB |
Output is correct |