#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll comb[63][33];
int N, M;
ll K;
char G[33][33];
string ans;
ll cc[33][33][63];
ll dp(int r, int c, int x) {
ll &ret = cc[r][c][x];
if(ret != -1) return ret;
ret = 0;
if(G[r][c] != ans[x]) return ret;
if(x == (int)ans.size() - 1) return ret = comb[N + M - 2 - r - c][M - 1 - c];
if(r < N) ret += dp(r + 1, c, x + 1);
if(c < M) ret += dp(r, c + 1, x + 1);
return ret;
}
ll calc() {
memset(cc, -1, sizeof(cc));
return dp(0, 0, 0);
}
int main() {
comb[0][0] = 1;
for(int i = 1; i < 63; i++) {
comb[i][0] = 1;
for(int j = 1; j <= i; j++) {
comb[i][j] = comb[i - 1][j - 1] + comb[i - 1][j];
}
}
std::ios::sync_with_stdio(false);
cin >> N >> M;
for(int i = 0; i < N; i++) {
for(int j = 0; j < M; j++) {
cin >> G[i][j];
}
}
cin >> K;
for(int i = 0; i < N + M; i++) {
for(int j = 0; j < 26; j++) {
ans.push_back('a' + j);
ll t = calc();
if(K <= t) break;
K -= t;
ans.pop_back();
}
}
cout << ans;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
3 ms |
512 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |