oj.uz

Submission #941706

# Submission time Handle Problem Language Result Execution time Memory
941706 2024-03-09T10:24:05 Z vjudge1 Building 4 (JOI20_building4) C++17
100 / 100
 269 ms 99888 KB 
#include <bits/stdc++.h>
using namespace std;

using ll = long long;
#define int ll

#define endl '\n'
#define pb push_back
using pi = array<int, 2>;
template<class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }

/*
iau mereu cel mai mic posibil si dau switch

daca v[i][min] <= v[i + 1][min] si v[i][max] >= v[i + 1][min] si v[i][max] <= v[i + 1][max] atunci daca schimb i, schimb si i+1

pot sa iau sufix la cel mai mare interval
sufixul e un interval de valori (se schimba cu 1 costul)
v[i][0] = minimu
v[i][1] = maximu

balance = A - B
*/

int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  
  int n;
  cin >> n;
  n *= 2;
  
  vector<bool> swappedv(n + 1), is_max(n + 1);
  vector<int> cost(n + 1);
  vector<vector<int>> v(n + 1, vector<int>(2));
  for (int i = 1; i <= n; ++i) cin >> v[i][0];
  for (int i = 1; i <= n; ++i) cin >> v[i][1];
  
  bool ok = true;
  int balance = 0, lastc = 0;
  for (int i = 1; i <= n; ++i) {
    if (v[i][0] <= v[i][1]) {
      if (v[i][0] >= lastc) {
        balance += 1;
        cost[i] = -1;
        
        lastc = v[i][0];
      } else {
        ok &= (v[i][1] >= lastc);
        balance -= 1;
        cost[i] = 0;
        is_max[i] = true;
        
        lastc = v[i][1];
      }
    } else {
      swappedv[i] = true;
      swap(v[i][0], v[i][1]);
      if (v[i][0] >= lastc) {
        balance -= 1;
        cost[i] = 1;
        
        lastc = v[i][0];
      } else {
        ok &= (v[i][1] >= lastc);
        balance += 1;
        cost[i] = 0;
        is_max[i] = true;
        
        lastc = v[i][1];
      }
    }
  }
  
  if (!ok) {
    cout << "-1";
    return 0;
  }
  balance /= 2;
  
  vector<pi> segments;
  int st = 1;
  for (int dr = 1; dr < n; ++dr) {
    if (cost[dr] == 0) { // sunt deja max
      segments.pb({st, dr});
      st = dr + 1;
      continue;
    }
    
    if (v[dr][1] > v[dr + 1][1]) { // nu pot da swap la asta, segmentul e invalidat
      st = dr + 1;
      continue;
    }
    
    if (v[dr][1] > v[dr + 1][0]) continue; // trebuie sa dau swap si la urmatorul
    
    // segmentul se termina aici
    segments.pb({st, dr});
    st = dr + 1;
  }
  segments.pb({st, n});
  
  /*cout << endl << endl;
  for (int i = 1; i <= n; ++i) cout << is_max[i] << " ";*/
  /*cout << endl << endl << balance << endl;
  for (pi s : segments) {
    cout << s[0] << " " << s[1] << " | ";
    for (int i = s[0]; i <= s[1]; ++i) cout << cost[i] << " ";
    cout << endl;
  }
  cout << endl;*/
  
  for (pi s : segments) {
    int l = s[0], r = s[1];
    
    int suf = 0;
    if (balance < 0) {
      int maxi = 0, maxidx = r + 1;
      for (int i = r; i >= l; --i) {
        suf += cost[i];
        if (balance + suf <= 0 && suf > maxi) {
          maxi = suf;
          maxidx = i;
        }
      }
      for (int i = r; i >= maxidx; --i) is_max[i] = true;
      
      balance += maxi;
    } else if (balance > 0) {
      int mini = 0, minidx = r + 1;
      for (int i = r; i >= l; --i) {
        suf += cost[i];
        if (balance + suf >= 0 && suf < mini) {
          mini = suf;
          minidx = i;
        }
      }
      for (int i = r; i >= minidx; --i) is_max[i] = true;
      
      balance += mini;
    }
  }
  
  if (balance != 0) {
    cout << "-1";
    return 0;
  }
  
  for (int i = 1; i <= n; ++i) {
    bool is_a = true;
    if (swappedv[i]) is_a = !is_a;
    if (is_max[i]) is_a = !is_a;
    cout << (is_a ? 'A' : 'B');
  }
}

/*
2
42 14 97 89 
30 68 69 53
*/

Subtask #1
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 1 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 1 ms 764 KB Output is correct
12 Correct 2 ms 784 KB Output is correct
13 Correct 2 ms 600 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 1 ms 752 KB Output is correct
17 Correct 1 ms 604 KB Output is correct
18 Correct 1 ms 600 KB Output is correct
19 Correct 2 ms 784 KB Output is correct
20 Correct 2 ms 600 KB Output is correct
21 Correct 1 ms 604 KB Output is correct
22 Correct 1 ms 860 KB Output is correct
23 Correct 1 ms 860 KB Output is correct
24 Correct 1 ms 604 KB Output is correct
25 Correct 1 ms 604 KB Output is correct
26 Correct 1 ms 720 KB Output is correct
27 Correct 1 ms 600 KB Output is correct
28 Correct 1 ms 604 KB Output is correct
29 Correct 1 ms 604 KB Output is correct
30 Correct 1 ms 600 KB Output is correct
31 Correct 1 ms 604 KB Output is correct
32 Correct 1 ms 604 KB Output is correct
33 Correct 2 ms 604 KB Output is correct

Subtask #2
89.0 / 89.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 604 KB Output is correct
6 Correct 1 ms 604 KB Output is correct
7 Correct 1 ms 604 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 604 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 1 ms 764 KB Output is correct
12 Correct 2 ms 784 KB Output is correct
13 Correct 2 ms 600 KB Output is correct
14 Correct 2 ms 860 KB Output is correct
15 Correct 1 ms 604 KB Output is correct
16 Correct 1 ms 752 KB Output is correct
17 Correct 1 ms 604 KB Output is correct
18 Correct 1 ms 600 KB Output is correct
19 Correct 2 ms 784 KB Output is correct
20 Correct 2 ms 600 KB Output is correct
21 Correct 1 ms 604 KB Output is correct
22 Correct 1 ms 860 KB Output is correct
23 Correct 1 ms 860 KB Output is correct
24 Correct 1 ms 604 KB Output is correct
25 Correct 1 ms 604 KB Output is correct
26 Correct 1 ms 720 KB Output is correct
27 Correct 1 ms 600 KB Output is correct
28 Correct 1 ms 604 KB Output is correct
29 Correct 1 ms 604 KB Output is correct
30 Correct 1 ms 600 KB Output is correct
31 Correct 1 ms 604 KB Output is correct
32 Correct 1 ms 604 KB Output is correct
33 Correct 2 ms 604 KB Output is correct
34 Correct 212 ms 81092 KB Output is correct
35 Correct 222 ms 85828 KB Output is correct
36 Correct 256 ms 84368 KB Output is correct
37 Correct 223 ms 85700 KB Output is correct
38 Correct 230 ms 94144 KB Output is correct
39 Correct 223 ms 81404 KB Output is correct
40 Correct 224 ms 92100 KB Output is correct
41 Correct 218 ms 78776 KB Output is correct
42 Correct 229 ms 80912 KB Output is correct
43 Correct 249 ms 91832 KB Output is correct
44 Correct 260 ms 92212 KB Output is correct
45 Correct 269 ms 91436 KB Output is correct
46 Correct 246 ms 99888 KB Output is correct
47 Correct 238 ms 88004 KB Output is correct
48 Correct 234 ms 86468 KB Output is correct
49 Correct 246 ms 92588 KB Output is correct
50 Correct 244 ms 90932 KB Output is correct
51 Correct 248 ms 91580 KB Output is correct
52 Correct 220 ms 79916 KB Output is correct
53 Correct 187 ms 80640 KB Output is correct
54 Correct 190 ms 88752 KB Output is correct
55 Correct 190 ms 88380 KB Output is correct
56 Correct 235 ms 83784 KB Output is correct
57 Correct 230 ms 78420 KB Output is correct
58 Correct 203 ms 78676 KB Output is correct
59 Correct 222 ms 78792 KB Output is correct
60 Correct 222 ms 74344 KB Output is correct
61 Correct 209 ms 79152 KB Output is correct
62 Correct 210 ms 78120 KB Output is correct
63 Correct 225 ms 79136 KB Output is correct
64 Correct 195 ms 76368 KB Output is correct
65 Correct 208 ms 79184 KB Output is correct