oj.uz

Submission #824492

# Submission time Handle Problem Language Result Execution time Memory
824492 2023-08-14T06:54:14 Z christinelynn Ekoeko (COCI21_ekoeko) C++17
110 / 110
 13 ms 3364 KB 
#include<bits/stdc++.h>
#define int long long
using namespace std;
int n;
int merge(vector<int> &a, int l, int r);
int number_of_inversions(vector<int> &a, int l=0, int r=n-1) {
  if(l>=r) return 0;
  int mid=l+r>>1, ret=0;
  ret+=number_of_inversions(a, l, mid);
  ret+=number_of_inversions(a, mid+1, r);
  ret+=merge(a, l, r);
  return ret;
}
int merge(vector<int> &a, int l, int r) {
  vector<int> temp(r-l+1);
  int mid=l+r>>1;
  int i=l, j=mid+1, k=0, ret=0;
  while(i<=mid && j<=r) {
    if(a[i]<=a[j]) temp[k++]=a[i++];
    else temp[k++]=a[j++], ret+=mid-i+1;
  }
  while(i<=mid) temp[k++]=a[i++];
  while(j<=r) temp[k++]=a[j++];
  for(int I=l; I<=r; I++) a[I]=temp[I-l];
  return ret;
}
signed main() {
  ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
  string s; 
  cin >> n >> s;
  vector<int> a, cnt(26);
  vector<deque<int>> idx(26);
  vector<bool> vis(2*n);
  for(char c : s) cnt[c-'a']++;
  for(int &p : cnt) p>>=1;
  int ans=0, pre=0;
  for(int i=0; i<2*n; i++) {
    if(cnt[s[i]-'a']) {
      cnt[s[i]-'a']--;
      vis[i]=1;
      idx[s[i]-'a'].push_back(i);
      ans+=pre;
    } else pre++;
  }
  for(int i=0; i<2*n; i++) {
    if(vis[i]) continue;
    a.push_back(idx[s[i]-'a'].front());
    idx[s[i]-'a'].pop_front();
  }
  ans+=number_of_inversions(a);
  cout << ans << '\n';
  return 0;
}

Compilation message

Main.cpp: In function 'long long int number_of_inversions(std::vector<long long int>&, long long int, long long int)':
Main.cpp:8:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
    8 |   int mid=l+r>>1, ret=0;
      |           ~^~
Main.cpp: In function 'long long int merge(std::vector<long long int>&, long long int, long long int)':
Main.cpp:16:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   16 |   int mid=l+r>>1;
      |           ~^~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 1236 KB Output is correct
3 Correct 5 ms 2268 KB Output is correct
4 Correct 8 ms 3340 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 1236 KB Output is correct
3 Correct 5 ms 2268 KB Output is correct
4 Correct 8 ms 3340 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 212 KB Output is correct

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 1236 KB Output is correct
3 Correct 5 ms 2268 KB Output is correct
4 Correct 8 ms 3340 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 11 ms 3272 KB Output is correct
7 Correct 11 ms 3284 KB Output is correct
8 Correct 11 ms 3284 KB Output is correct
9 Correct 11 ms 3176 KB Output is correct
10 Correct 11 ms 3156 KB Output is correct
11 Correct 13 ms 3144 KB Output is correct
12 Correct 11 ms 3160 KB Output is correct
13 Correct 10 ms 3104 KB Output is correct
14 Correct 10 ms 3036 KB Output is correct
15 Correct 11 ms 3048 KB Output is correct

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 340 KB Output is correct
3 Correct 1 ms 340 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 0 ms 340 KB Output is correct
6 Correct 0 ms 340 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 0 ms 340 KB Output is correct
9 Correct 0 ms 340 KB Output is correct
10 Correct 0 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct

Subtask #5
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 2 ms 1236 KB Output is correct
3 Correct 5 ms 2268 KB Output is correct
4 Correct 8 ms 3340 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 0 ms 212 KB Output is correct
10 Correct 11 ms 3272 KB Output is correct
11 Correct 11 ms 3284 KB Output is correct
12 Correct 11 ms 3284 KB Output is correct
13 Correct 11 ms 3176 KB Output is correct
14 Correct 11 ms 3156 KB Output is correct
15 Correct 13 ms 3144 KB Output is correct
16 Correct 11 ms 3160 KB Output is correct
17 Correct 10 ms 3104 KB Output is correct
18 Correct 10 ms 3036 KB Output is correct
19 Correct 11 ms 3048 KB Output is correct
20 Correct 0 ms 212 KB Output is correct
21 Correct 0 ms 340 KB Output is correct
22 Correct 1 ms 340 KB Output is correct
23 Correct 0 ms 340 KB Output is correct
24 Correct 0 ms 340 KB Output is correct
25 Correct 0 ms 340 KB Output is correct
26 Correct 1 ms 340 KB Output is correct
27 Correct 0 ms 340 KB Output is correct
28 Correct 0 ms 340 KB Output is correct
29 Correct 0 ms 340 KB Output is correct
30 Correct 1 ms 340 KB Output is correct
31 Correct 0 ms 212 KB Output is correct
32 Correct 12 ms 3364 KB Output is correct
33 Correct 12 ms 3340 KB Output is correct
34 Correct 11 ms 3328 KB Output is correct
35 Correct 12 ms 3284 KB Output is correct
36 Correct 11 ms 3156 KB Output is correct
37 Correct 11 ms 3160 KB Output is correct
38 Correct 11 ms 3132 KB Output is correct
39 Correct 11 ms 3164 KB Output is correct
40 Correct 11 ms 3060 KB Output is correct
41 Correct 11 ms 3044 KB Output is correct