#include "bits/stdc++.h"
using namespace std;
#ifdef N_N_C
#include "debug.h"
#else
#define cebug(...) "Arya"
#endif
#define ll long long
const int N=1e5+5;
const int mod=1e9+7;
int n,node=1,a[N],sz[N],ans[N],cur;
vector <int> g[N];
struct BIT{
#define gb(x) (x&(-x))
int n;
vector <int> bit;
void init(int _n){
bit.resize(_n,0);
n=_n;
}
void update(int pos, int val){
int i=pos;
for (; i<=n; i+=gb(i)) bit[i]+=val;
}
int get(int pos){
int ans=0,i=pos;
for (; i>=1; i-=gb(i)) ans+=bit[i];
return ans;
}
}fw;
void input(){
int x;
cin>>x;
a[node]=x;
if(x) return;
int nw=node;
g[nw].push_back(++node);
input();
g[nw].push_back(++node);
input();
}
void pre_dfs(int u){
sz[u]=1;
for(auto v:g[u]){
pre_dfs(v);
sz[u]+=sz[v];
}
}
void add(int u){
if(a[u]) cur+=fw.get(a[u]-1);
for(auto v:g[u]) add(v);
}
void del(int u){
if(a[u]) fw.update(a[u]+1,-1);
for(auto v:g[u]) del(v);
}
void upd(int u){
if(a[u]) fw.update(a[u]+1,1);
for(auto v:g[u]) upd(v);
}
void dfs(int u){
if(a[u]){
fw.update(a[u],1);
return;
}
int big=0;
cur=0;
for(auto v:g[u]) if(sz[v]>sz[big]) big=v;
for(auto v:g[u]){
if(v!=big){
dfs(v);
del(v);
ans[u]+=ans[v];
}
}
assert(big);
dfs(big);
ans[u]+=ans[big];
for(auto v:g[u]) if(v!=big) add(v);
ans[u]+=min(cur,sz[u]*(sz[u]-1)/2-cur);
}
void sol(){
fw.init(N);
cin>>n;
input();
pre_dfs(1);
dfs(1);
cout<<ans[1];
}
signed main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
// freopen(".inp", "r", stdin);
// freopen(".out", "w", stdout);
int tt=1;
//cin>>tt;
while(tt--){
sol();
}
cerr << "\nTime elapsed: " << 1000.0 * clock() / CLOCKS_PER_SEC << " ms.\n";
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
3164 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
1 ms |
3160 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
3164 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
3 ms |
3676 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
6 ms |
4700 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
16 ms |
10332 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
17 ms |
17820 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
17 ms |
10876 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
12 ms |
10588 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
13 ms |
12124 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
13 ms |
11864 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |