#include<bits/stdc++.h>
using namespace std;
int freq[200];
const int maxn = 200001;
vector<char>exclnt;
deque<int>dex[200];
vector<int>ord;
int segtree[4*maxn]={0};
void update(int idx, int low, int high, int val) {
if(low==val && high==val) {
segtree[idx]=1;
return;
}
if(val<low || val>high) {
return;
}
int mid = (low+high)/2;
update(2*idx,low,mid,val);
update(2*idx+1, mid+1,high,val);
segtree[idx] = segtree[2*idx] + segtree[2*idx+1];
}
int quer(int idx, int low, int high, int l, int r) {
if(low>=l && high<=r) {
return segtree[idx];
}
if(low>r || high<l) return 0;
int mid = (low+high)/2;
return quer(2*idx,low,mid,l,r)+quer(2*idx+1,mid+1,high,l,r);
}
int main() {
int n;
string gab;
cin >> n;
cin >> gab;
n = n*2;
for(int i=0; i<n; i++) {
int x = gab[i]-97;
freq[x]++;
}
for(int i=0; i<n; i++) {
int x = gab[i]-97;
if(freq[x] > 0) {
exclnt.push_back(gab[i]);
freq[x]-=2;
}
}
int ukex = exclnt.size();
for(int i=0; i<ukex; i++) {
exclnt.push_back(exclnt[i]);
}
for(int i=0; i<n; i++) {
int x = exclnt[i]-97;
dex[x].push_back(i);
}
for(int i=0; i<n; i++) {
int x = gab[i]-97;
ord.push_back(dex[x].front());
dex[x].pop_front();
}
int ans=0;
for(int i=0; i<n; i++) {
ans+=quer(1,1,n-1,ord[i],n-1);
update(1,1,n-1,ord[i]);
}
cout << ans << endl;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
19 ms |
2284 KB |
Output is correct |
3 |
Correct |
35 ms |
4060 KB |
Output is correct |
4 |
Incorrect |
49 ms |
4728 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
19 ms |
2284 KB |
Output is correct |
3 |
Correct |
35 ms |
4060 KB |
Output is correct |
4 |
Incorrect |
49 ms |
4728 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
19 ms |
2284 KB |
Output is correct |
3 |
Correct |
35 ms |
4060 KB |
Output is correct |
4 |
Incorrect |
49 ms |
4728 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
1 ms |
468 KB |
Output is correct |
3 |
Correct |
1 ms |
468 KB |
Output is correct |
4 |
Correct |
1 ms |
468 KB |
Output is correct |
5 |
Correct |
1 ms |
468 KB |
Output is correct |
6 |
Correct |
1 ms |
468 KB |
Output is correct |
7 |
Correct |
1 ms |
356 KB |
Output is correct |
8 |
Correct |
1 ms |
468 KB |
Output is correct |
9 |
Correct |
1 ms |
468 KB |
Output is correct |
10 |
Correct |
1 ms |
468 KB |
Output is correct |
11 |
Correct |
1 ms |
468 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
340 KB |
Output is correct |
2 |
Correct |
19 ms |
2284 KB |
Output is correct |
3 |
Correct |
35 ms |
4060 KB |
Output is correct |
4 |
Incorrect |
49 ms |
4728 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |