Submission #824491

# Submission time Handle Problem Language Result Execution time Memory
824491 2023-08-14T06:53:52 Z yusuf12360 Ekoeko (COCI21_ekoeko) C++14
110 / 110
16 ms 3572 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:8:11: 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:16:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   16 |  int mid=l+r>>1;
      |          ~^~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 4 ms 1364 KB Output is correct
3 Correct 6 ms 2492 KB Output is correct
4 Correct 7 ms 3540 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 4 ms 1364 KB Output is correct
3 Correct 6 ms 2492 KB Output is correct
4 Correct 7 ms 3540 KB Output is correct
5 Correct 1 ms 320 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 292 KB Output is correct
8 Correct 1 ms 324 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 4 ms 1364 KB Output is correct
3 Correct 6 ms 2492 KB Output is correct
4 Correct 7 ms 3540 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 12 ms 3528 KB Output is correct
7 Correct 14 ms 3412 KB Output is correct
8 Correct 11 ms 3404 KB Output is correct
9 Correct 14 ms 3412 KB Output is correct
10 Correct 11 ms 3404 KB Output is correct
11 Correct 11 ms 3288 KB Output is correct
12 Correct 11 ms 3280 KB Output is correct
13 Correct 11 ms 3296 KB Output is correct
14 Correct 11 ms 3244 KB Output is correct
15 Correct 13 ms 3252 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 1 ms 320 KB Output is correct
4 Correct 0 ms 340 KB Output is correct
5 Correct 1 ms 328 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 316 KB Output is correct
9 Correct 1 ms 320 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 4 ms 1364 KB Output is correct
3 Correct 6 ms 2492 KB Output is correct
4 Correct 7 ms 3540 KB Output is correct
5 Correct 1 ms 320 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 1 ms 292 KB Output is correct
8 Correct 1 ms 324 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 12 ms 3528 KB Output is correct
11 Correct 14 ms 3412 KB Output is correct
12 Correct 11 ms 3404 KB Output is correct
13 Correct 14 ms 3412 KB Output is correct
14 Correct 11 ms 3404 KB Output is correct
15 Correct 11 ms 3288 KB Output is correct
16 Correct 11 ms 3280 KB Output is correct
17 Correct 11 ms 3296 KB Output is correct
18 Correct 11 ms 3244 KB Output is correct
19 Correct 13 ms 3252 KB Output is correct
20 Correct 1 ms 340 KB Output is correct
21 Correct 1 ms 340 KB Output is correct
22 Correct 1 ms 320 KB Output is correct
23 Correct 0 ms 340 KB Output is correct
24 Correct 1 ms 328 KB Output is correct
25 Correct 1 ms 340 KB Output is correct
26 Correct 1 ms 348 KB Output is correct
27 Correct 1 ms 316 KB Output is correct
28 Correct 1 ms 320 KB Output is correct
29 Correct 1 ms 340 KB Output is correct
30 Correct 1 ms 340 KB Output is correct
31 Correct 1 ms 324 KB Output is correct
32 Correct 12 ms 3572 KB Output is correct
33 Correct 11 ms 3520 KB Output is correct
34 Correct 15 ms 3528 KB Output is correct
35 Correct 16 ms 3356 KB Output is correct
36 Correct 11 ms 3388 KB Output is correct
37 Correct 12 ms 3332 KB Output is correct
38 Correct 16 ms 3280 KB Output is correct
39 Correct 15 ms 3264 KB Output is correct
40 Correct 10 ms 3248 KB Output is correct
41 Correct 11 ms 3220 KB Output is correct