#include<bits/stdc++.h>
#define fi first
#define se second
using namespace std;
const int N=1e6;
vector<int> e[N+10];
int f[N+10];
int l[N+10];
bitset<N+10> vis_fill;
bitset<N+10> vis_s;
bitset<N+10> on_cycle;
vector<int> t;
void dfs_fill(int x)
{
t.push_back(x);
vis_fill[x]=true;
for(auto v:e[x])
{
if(!vis_fill[v])
dfs_fill(v);
}
return;
}
long long aa;
long long dfs_tree(int x)
{
on_cycle[x]=true;
long long ans=0;
for(auto v:e[x])
{
if(on_cycle[v])
continue;
auto tmp=dfs_tree(v);
aa=max(aa,ans+tmp+(v==f[x] ? l[x]:l[v]));
ans=max(ans,tmp+(v==f[x] ? l[x]:l[v]));
}
return ans;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
int n;
cin>>n;
for(int i=1;i<=n;i++)
{
cin>>f[i]>>l[i];
e[i].push_back(f[i]);
e[f[i]].push_back(i);
}
long long ans=0;
for(int j=1;j<=n;j++)
{
if(!vis_fill[j])
{
t.clear();
dfs_fill(j);
long long ans_s=0;
int c;
for(int i=t[0];true;i=f[i])
{
if(vis_s[i])
{
c=i;
break;
}
vis_s[i]=true;
}
long long l_all=l[c];
on_cycle[c]=true;
for(int i=f[c];i!=c;l_all+=l[i],i=f[i])
on_cycle[i]=true;
long long mx=0,mn=0;
int x=c;
do{
x=f[x];
aa=0;
long long ww=dfs_tree(x);
ans_s=max(ans_s,aa);
ans_s=max({ans_s,mx+ww,mn+ww});
mx=max(mx,ww)+l[x];
mn=max(mn,ww+l_all)-l[x];
}while(x!=c);
ans+=ans_s;
}
}
cout<<ans<<"\n";
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
15 ms |
23756 KB |
Output is correct |
2 |
Correct |
15 ms |
23792 KB |
Output is correct |
3 |
Correct |
13 ms |
23756 KB |
Output is correct |
4 |
Correct |
13 ms |
23756 KB |
Output is correct |
5 |
Correct |
14 ms |
23756 KB |
Output is correct |
6 |
Correct |
16 ms |
23756 KB |
Output is correct |
7 |
Correct |
13 ms |
23752 KB |
Output is correct |
8 |
Correct |
13 ms |
23756 KB |
Output is correct |
9 |
Correct |
13 ms |
23756 KB |
Output is correct |
10 |
Correct |
14 ms |
23756 KB |
Output is correct |
11 |
Correct |
14 ms |
23832 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
14 ms |
23884 KB |
Output is correct |
2 |
Correct |
14 ms |
23884 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
14 ms |
23788 KB |
Output is correct |
2 |
Correct |
16 ms |
24140 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
20 ms |
24524 KB |
Output is correct |
2 |
Correct |
32 ms |
26552 KB |
Output is correct |
3 |
Correct |
24 ms |
24872 KB |
Output is correct |
4 |
Correct |
19 ms |
24268 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
36 ms |
27340 KB |
Output is correct |
2 |
Correct |
48 ms |
28996 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
93 ms |
34260 KB |
Output is correct |
2 |
Correct |
97 ms |
38168 KB |
Output is correct |
3 |
Correct |
117 ms |
44100 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
153 ms |
40916 KB |
Output is correct |
2 |
Correct |
198 ms |
58188 KB |
Output is correct |
3 |
Correct |
220 ms |
65412 KB |
Output is correct |
4 |
Correct |
275 ms |
77360 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
379 ms |
73400 KB |
Output is correct |
2 |
Correct |
827 ms |
99724 KB |
Output is correct |
3 |
Correct |
298 ms |
57176 KB |
Output is correct |
4 |
Correct |
402 ms |
84800 KB |
Output is correct |
5 |
Correct |
417 ms |
86504 KB |
Output is correct |
6 |
Correct |
1094 ms |
66616 KB |
Output is correct |
7 |
Correct |
419 ms |
104708 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Runtime error |
424 ms |
131076 KB |
Execution killed with signal 9 |
2 |
Halted |
0 ms |
0 KB |
- |