#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
#define float long double
// const int MOD=1e9+7;
const int MOD=998244353;
const int sqn=450;
const long double eps=1e-6;
const int dx[4]={0,0,1,-1};
const int dy[4]={1,-1,0,0};
long long power(long long a,long long b,long long p=MOD){
long long res=1;
while (b>0){
if (b%2==1) res=(res*a)%p;
b/=2;
a=(a*a)%p;
}
return res;
}
int n,m,sum;
vector<int> adj[1001],children[1001];
vector<pair<pair<int,int>,int> > edges[1001];
int twok[1001][11],depth[1001],childid[1001];
void dfsfill(int x,int p,int dd){
twok[x][0]=p;
depth[x]=dd;
for (int i=1;i<11;i++){
if (twok[x][i-1]==-1) break;
twok[x][i]=twok[twok[x][i-1]][i-1];
}
int id=0;
for (auto i:adj[x]){
if (i==p) continue;
dfsfill(i,x,dd+1);
children[x].pb(i);
childid[i]=id;
id++;
}
}
int lcaa(int a,int b){
if (depth[a]<depth[b]) swap(a,b);
int dd=depth[a]-depth[b];
for (int i=0;i<11;i++){
if (dd&(1<<i)){
a=twok[a][i];
}
}
if (a==b) return a;
for (int i=10;i>=0;i--){
if (twok[a][i]!=twok[b][i]){
a=twok[a][i];
b=twok[b][i];
}
}
return twok[a][0];
}
// start from graph containing only tree edges
// add max weight nontree edges without even cycles
// tree path of edge (A,B) consists of only tree edges
// odd/even edges have odd/even length tree path
// we can only take even edges
// no 2 nontree edges can have tree path overlap
// otherwise, odd path 1 + odd path 2 - overlap * 2 = even
// hence, each tree edge is in max 1 odd cycle
// we solve for every subtree
// dp[index][mask] = max weight we can take
// index = subtree root
// mask = which of the root's children is removed
// basically we have a tree
// each nontree edge is like placing a weight on a path
// we need to maximise the sum of weights without overlaps
int dp[1001][1024];
void dfs(int x){
for (auto i:children[x]){
dfs(i);
}
int sz=children[x].size();
for (int i=0;i<(1<<sz);i++){
for (int j=0;j<sz;j++){
if (i&(1<<j)) continue;
// since mask is who we want to exclude
dp[x][i]+=dp[children[x][j]][0];
}
}
for (auto edge:edges[x]){
int a=edge.first.first;
int b=edge.first.second;
int cur=edge.second;
int maska=0;
while (a!=x){
cur+=dp[a][maska];
maska=(1<<childid[a]);
a=twok[a][0];
}
int maskb=0;
while (b!=x){
cur+=dp[b][maskb];
maskb=(1<<childid[b]);
b=twok[b][0];
}
int mask=maska|maskb;
for (int i=0;i<(1<<sz);i++){
if (i&mask) continue;
dp[x][i]=max(dp[x][i],cur+dp[x][i|mask]);
}
}
}
void runtc(){
cin>>n>>m;
for (int i=1;i<=m;i++){
int a,b,c;
cin>>a>>b>>c;
if (c==0){
adj[a].pb(b);
adj[b].pb(a);
}
else {
edges[0].pb(mp(mp(a,b),c));
}
sum+=c;
}
dfsfill(1,-1,0);
for (auto i:edges[0]){
int a=i.first.first;
int b=i.first.second;
int c=i.second;
if ((depth[a]%2)!=(depth[b]%2)) continue;
int lca=lcaa(a,b);
edges[lca].pb(mp(mp(a,b),c));
}
dfs(1);
cout<<sum-dp[1][0];
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
// freopen("movie.in","r",stdin);
// freopen("movie.out","w",stdout);
// freopen("input1.in","r",stdin);
// freopen("output1.out","w",stdout);
//freopen("tower_rush_input.txt","r",stdin);
//freopen("hackercup_output.txt","w",stdout);
int tcs;
// cin>>tcs;
tcs=1;
for (int i=1;i<=tcs;i++){
// cout<<"Case #"<<i<<": ";
runtc();
}
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
600 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
2648 KB |
Output is correct |
2 |
Correct |
1 ms |
2652 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
4700 KB |
Output is correct |
2 |
Correct |
4 ms |
4700 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
344 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
604 KB |
Output is correct |
2 |
Correct |
0 ms |
604 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
856 KB |
Output is correct |
2 |
Correct |
1 ms |
860 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
1116 KB |
Output is correct |
2 |
Correct |
1 ms |
2652 KB |
Output is correct |
3 |
Correct |
2 ms |
1628 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
3420 KB |
Output is correct |
2 |
Correct |
3 ms |
1152 KB |
Output is correct |
3 |
Correct |
3 ms |
1456 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
844 KB |
Output is correct |
2 |
Correct |
1 ms |
1700 KB |
Output is correct |
3 |
Correct |
6 ms |
4700 KB |
Output is correct |
4 |
Correct |
2 ms |
1884 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
3 ms |
2148 KB |
Output is correct |
2 |
Correct |
7 ms |
4700 KB |
Output is correct |
3 |
Correct |
4 ms |
3348 KB |
Output is correct |
4 |
Correct |
3 ms |
1372 KB |
Output is correct |