/**
* Author: Anil Byar
**/
#include <bits/stdc++.h>
// #include <ext/pb_ds/assoc_container.hpp>
// #include <ext/pb_ds/tree_policy.hpp>
// using namespace __gnu_pbds;
using namespace std;
// template<class T>
// using ordered_set = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)(x).size()
#define uniq(v) v.erase(unique(all(v)), v.end())
#define ft first
#define sd second
#define pb push_back
#define eb emplace_back
// Source: https://codeforces.com/blog/entry/68809
// { start
void __print(int x) {cerr << x;}
void __print(long x) {cerr << x;}
void __print(long long x) {cerr << x;}
void __print(unsigned x) {cerr << x;}
void __print(unsigned long x) {cerr << x;}
void __print(unsigned long long x) {cerr << x;}
void __print(float x) {cerr << x;}
void __print(double x) {cerr << x;}
void __print(long double x) {cerr << x;}
void __print(char x) {cerr << '\'' << x << '\'';}
void __print(const char *x) {cerr << '"' << x << '"';}
void __print(const string &x) {cerr << '"' << x << '"';}
void __print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V>
void __print(const pair<T, V> &x) {cerr << '{'; __print(x.first); cerr << ','; __print(x.second); cerr << '}';}
template<typename T>
void __print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), __print(i); cerr << "}";}
void _print() {cerr << "]\n";}
template <typename T, typename... V>
void _print(T t, V... v) {__print(t); if (sizeof...(v)) cerr << ", "; _print(v...);}
#ifndef ONLINE_JUDGE
#define debug(x...) cerr << "[" << #x << "] = ["; _print(x)
#else
#define debug(x...)
#endif
// } end
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<pll> vll;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
typedef vector<vl> vvl;
#define dbg if(0)
const ll MOD = 1e9+7;
const ll MOD9 = 998244353;
const ll INFLL = 1e18+5;
const int INF = 1e9;
void printbit(int x, int len) {string s="\n";while(len--){s=((x%2)?'1':'0')+s;x/=2;} cout<<s;}
ll power(ll x, ll y, ll mod){if (y==0) return 1;ll ret = power(x, y/2, mod);ret *= ret;ret%=mod;if (y&1) ret *= x;return ret%mod;}
ll modinv(ll x, ll mod = MOD) {return power(x, mod-2, mod);}
template<class T>
istream& operator>>(istream&in, vector<T>&v){
for (T& x:v) in>>x;
return in;
}
template<class T>
ostream& operator<<(ostream&out, vector<T>&v){
for (T& x:v) out<<x<<' ';
cout<<'\n';
return out;
}
// use ?: with brackets (?:)
// check for overflow
// think about dp
// Read the statement carefully
const int N = 10001;
vii adj[N];
int n, k, x;
int dp[N][2][N];
int stree[N];
void dfs(int node, int par){
dp[node][0][0] = dp[node][1][0] = 0;
dp[node][0][1] = dp[node][1][1] = 0;
for (int i = 0;i<sz(adj[node]);i++){
auto z = adj[node][i];
assert(find(all(adj[z.ft]), make_pair(node, z.sd))!=adj[z.ft].end());
adj[z.ft].erase(find(all(adj[z.ft]), make_pair(node, z.sd)));
dfs(z.ft, node);
for (int j = 0;j<=stree[node];j++){
for (int l = 0;l<=stree[z.ft];l++){
dp[node][0][j+l] = min(dp[node][0][j+l], min(dp[node][0][j]+dp[z.ft][1][l] + 2*z.sd, dp[node][1][j]+dp[z.ft][0][l]+z.sd));
dp[node][1][j+l] = min(dp[node][1][j+l], dp[node][1][j]+dp[z.ft][1][l]+2*z.sd);
}
}
stree[node] += stree[z.ft];
for (int j = 0;j<=stree[node];j++) {
tmp[0][j] = dp[node][0][j];
tmp[1][j] = dp[node][1][j];
}
}
}
void solve(){
cin>>n>>k>>x;
for (int i = 0;i<n-1;i++){
int u, v, w;cin>>u>>v>>w;
adj[u].eb(v, w);
adj[v].eb(u, w);
}
memset(dp, 63, sizeof(dp));
dfs(x, -1);
cout<<dp[x][0][k];
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
freopen("input.in", "r", stdin);
freopen("output.out", "w", stdout);
freopen("debug.dbg", "w", stderr);
int tt = clock();
#endif
int t=1, i = 1;
// cin>>t;
while(t--){
// cout<<"Case #"<<i++<<": ";
solve();
cout<<'\n';
}
#ifndef ONLINE_JUDGE
cerr << "TIME = " << (float)(clock() - tt)/CLOCKS_PER_SEC << endl;
tt = clock();
#endif
}
Compilation message
museum.cpp: In function 'void dfs(int, int)':
museum.cpp:120:4: error: 'tmp' was not declared in this scope; did you mean 'tm'?
120 | tmp[0][j] = dp[node][0][j];
| ^~~
| tm
museum.cpp: In function 'int main()':
museum.cpp:152:11: warning: unused variable 'i' [-Wunused-variable]
152 | int t=1, i = 1;
| ^
