oj.uz

Submission #523305

# Submission time Handle Problem Language Result Execution time Memory
523305 2022-02-07T11:20:56 Z Pety K-th path (IZhO11_kthpath) C++14
100 / 100
 1 ms 332 KB 
#include <bits/stdc++.h>
#define ll long long

using namespace std;

const ll INF = 1e18;
const int MOD = 1e9 + 7;

ifstream fin ("hyper.in");
ofstream fout ("hyper.out");

int n, m, viz[32][32], cnt[32][32];
ll comb[62][62];
ll k;
char ch[32][32];
deque<pair<int, int>>q;

int dl[4] = {0, 0, -1, 1};
int dc[4] = {1, -1, 0, 0};


int main () 
{
  //ios_base::sync_with_stdio(false);
  //cin.tie(0); cout.tie(0);
  cin >> n >> m;
  for (int i = 1; i <= n; i++)
    for (int j = 1; j <= m; j++)
      cin >> ch[i][j];
  for (int i = 0; i <= n + m; i++) {
    comb[i][0] = comb[i][i] = 1;
    for (int j = 1; j < i; j++)
      comb[i][j] = min(INF, comb[i - 1][j] + comb[i - 1][j - 1]);
  }
  cin >> k;
  viz[1][1] = 1;
  cnt[1][1] = 1;
  q.push_back({1, 1});
  for (int pas = 1; pas <= n + m - 1; pas++) {
    vector<ll>nr(26);
    for (auto p: q) {
      if (INF / cnt[p.first][p.second] < comb[n - p.first + m - p.second][n - p.first])
        nr[ch[p.first][p.second] - 'a'] += INF;
      else 
        nr[ch[p.first][p.second] - 'a'] += 1ll * cnt[p.first][p.second] * comb[n - p.first + m - p.second][n - p.first]; 
      nr[ch[p.first][p.second] - 'a'] = min(nr[ch[p.first][p.second] - 'a'], INF);
    }
    //cout << cnt[3][2] << "\n";
    for (int j = 1; j < 26; j++)
      nr[j] = min(INF, nr[j] + nr[j - 1]);
    char letter = 'z' + 1;
    for (int j = 0; j < 26; j++)
      if (k <= nr[j]) {
        letter = j + 'a';
        k -= (j == 0 ? 0 : nr[j - 1]);
        break;
      }
 //   if (letter == 'z' + 1) {
   //   cout << k << "\n";
    //}
    cout << letter;
    int sz = q.size();
    for (int i = 1; i <= sz; i++) {
      auto p = q.front();
      q.pop_front();
      if (ch[p.first][p.second] != letter)
        continue;
      for (int k = 0; k < 4; k++) {
        int x = p.first + dl[k];
        int y = p.second + dc[k];
        if (x >= 1 && x <= n && y >= 1 && y <= m && x - 1 + y -1 == pas) {
          if (!viz[x][y]) {
            q.push_back({x, y});
            viz[x][y] = 1;
            cnt[x][y] += cnt[p.first][p.second];
          }
          else
            cnt[x][y]+=cnt[p.first][p.second];
        } 
      }
    }
  }
    
  return 0;
}

Subtask #1
100.0 / 100.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 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 0 ms 332 KB Output is correct
6 Correct 1 ms 332 KB Output is correct
7 Correct 0 ms 332 KB Output is correct
8 Correct 0 ms 332 KB Output is correct
9 Correct 1 ms 308 KB Output is correct
10 Correct 1 ms 332 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 312 KB Output is correct
14 Correct 1 ms 332 KB Output is correct
15 Correct 1 ms 332 KB Output is correct
16 Correct 1 ms 308 KB Output is correct
17 Correct 1 ms 312 KB Output is correct
18 Correct 1 ms 304 KB Output is correct
19 Correct 1 ms 332 KB Output is correct
20 Correct 1 ms 332 KB Output is correct