#include <bits/stdc++.h>
#define MN 37
using namespace std;
using ll = long long;
ll n, m, k;
char A[MN][MN];
string sol;
ll DP[MN][MN][3];// < = >
ll nr() {
///raspunde in O(n * m)
DP[n][m][0] = (sol[n + m - 2] > A[n][m]);
DP[n][m][1] = (sol[n + m - 2] == A[n][m]);
DP[n][m][2] = (sol[n + m - 2] < A[n][m]);
for (ll i = n; i >= 1; --i) {
for (ll j = m - (i == n); j >= 1; --j) {
if (sol[i + j - 2] > A[i][j])
DP[i][j][0] = DP[i + 1][j][0] + DP[i + 1][j][1] + DP[i + 1][j][2] +
DP[i][j + 1][0] + DP[i][j + 1][1] + DP[i][j + 1][2],
DP[i][j][1] = 0,
DP[i][j][2] = 0;
else if (sol[i + j - 2] < A[i][j])
DP[i][j][0] = 0,
DP[i][j][1] = 0,
DP[i][j][2] = DP[i + 1][j][0] + DP[i + 1][j][1] + DP[i + 1][j][2] +
DP[i][j + 1][0] + DP[i][j + 1][1] + DP[i][j + 1][2];
else
DP[i][j][0] = DP[i + 1][j][0] + DP[i][j + 1][0],
DP[i][j][1] = DP[i + 1][j][1] + DP[i][j + 1][1],
DP[i][j][2] = DP[i + 1][j][2] + DP[i][j + 1][2];
}
}
return DP[1][1][0] + DP[1][1][1];
}
ll mi_greedy(ll p) {
///daca ar fi sa completez cu 'a' restul string-ului, care ar fi rez?
for (ll i = p; i < n + m - 1; ++i) sol[i] = 'a';
return nr();
}
ll ma_greedy(ll p) {
///daca ar fi sa completez cu 'z' restul string-ului, care ar fi rez?
for (ll i = p; i < n + m - 1; ++i) sol[i] = 'z';
return nr();
}
void gen(int p) {
if (p == n + m) return;
char st = 'a', dr = 'z', mij;
while (st < dr) {
mij = (st + dr) / 2;
sol[p] = mij;
if (ma_greedy(p + 1) < k) st = mij + 1;
else dr = mij;
}
sol[p] = st;
gen(p + 1);
}
int main() {
cin >> n >> m;
sol.assign(n + m - 1, 'a');
for (int i = 1; i <= n; ++i)
for (int j = 1; j <= m; ++j)
cin >> A[i][j];
///caut primul string cu nr(s) >= k
cin >> k;
gen(0);
cout << sol << "\n";
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
204 KB |
Output is correct |
2 |
Correct |
0 ms |
204 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
1 ms |
204 KB |
Output is correct |
5 |
Correct |
1 ms |
204 KB |
Output is correct |
6 |
Correct |
0 ms |
204 KB |
Output is correct |
7 |
Correct |
1 ms |
204 KB |
Output is correct |
8 |
Correct |
1 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
1 ms |
204 KB |
Output is correct |
11 |
Correct |
1 ms |
204 KB |
Output is correct |
12 |
Correct |
1 ms |
204 KB |
Output is correct |
13 |
Correct |
1 ms |
304 KB |
Output is correct |
14 |
Correct |
1 ms |
204 KB |
Output is correct |
15 |
Correct |
1 ms |
204 KB |
Output is correct |
16 |
Correct |
1 ms |
204 KB |
Output is correct |
17 |
Correct |
1 ms |
332 KB |
Output is correct |
18 |
Correct |
1 ms |
204 KB |
Output is correct |
19 |
Correct |
1 ms |
332 KB |
Output is correct |
20 |
Correct |
1 ms |
204 KB |
Output is correct |