Submission #641424

#	Time	Username	Problem	Language	Result	Execution time	Memory
641424		DragonO_o	Paths (RMI21_paths)	C++17	36 / 100	1081 ms	18596 KiB

Main

#pragma GCC optimize("Ofast")
//#pragma GCC optimize("O3,unroll-loops")
//#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
//#pragma GCC optimize("inline,Ofast,no-stack-protector,unroll-loops,fast-math,O3")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4.1,sse4.2,popcnt,avx,abm")

#include <bits/stdc++.h>

using namespace std;

//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
//using namespace __gnu_pbds;
//#define ordered_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>

#define sz(x) (int)(x).size()
#define int long long
#define FOR(i,l,r) for(int i=l;i<=(r);++i)
#define FORd(i,r,l) for(int i=r;i>=(l);--i)
#define pb push_back
#define x first
#define y second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(),x.end()
#define ins insert

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
typedef pair<int,int>pii;
typedef pair<ll,ll>pll;
typedef vector<ll>vll;
typedef vector<int>vi;
typedef vector<bool>vb;
typedef vector<vi>vvi;
typedef vector<vll>vvll;
typedef vector<pii>vpii;
typedef vector<pll>vpll;

const int N=2e5+25;
const int MOD=1e9+7;
const int INF=1e18;
const char nl='\n';

int n,k;
vpii g[N];
int dist[N];
int down[N];
int up[N];

void pre_calc1(int v,int p){
    for(auto [to,w]:g[v]){
        if(to!=p){
            dist[to]=dist[v]+w;
            pre_calc1(to,v);
        }
    }
    down[v]=v;
    for(auto [to,w]:g[v]){
        if(to!=p){
            if(dist[down[to]]>=dist[down[v]]){
                down[v]=down[to];
            }
        }
    }
}

void pre_calc2(int v,int p){
    set<pii,greater<pii>>st;
    for(auto [to,w]:g[v]){
        if(to!=p){
            st.insert({dist[down[to]]-dist[v],down[to]});
        }
    }
    for(auto [to,w]:g[v]){
        if(to!=p){
            up[to]=up[v];
            st.erase({dist[down[to]]-dist[v],down[to]});
            pii best=*st.begin();
            if(!st.empty() && w+best.x>dist[to]+dist[up[to]]){
                up[to]=best.y;
            }
            st.insert({dist[down[to]]-dist[v],down[to]});
        }
    }
    for(auto [to,w]:g[v]){
        if(to!=p){
            pre_calc2(to,v);
        }
    }
}

int a[N];
int val[N];
multiset<int,greater<int>>take,rest;

void dfs(int v,int p){
    if(!a[down[v]]){
        a[down[v]]=p;
        val[down[v]]=dist[down[v]]-dist[p];
        rest.insert(val[down[v]]);
    }
    for(auto [to,w]:g[v]){
        if(to!=p){
            dfs(to,v);
        }
    }
}

void solve(){
    cin>>n>>k;
    for(int i=1;i<n;++i){
        int u,v,w;
        cin>>u>>v>>w;
        g[u].pb({v,w});
        g[v].pb({u,w});
    }
    for(int root=1;root<=n;++root){
        for(int i=1;i<=n;++i){
            dist[i]=down[i]=up[i]=a[i]=val[i]=0;
        }
        take.clear();
        rest.clear();
        pre_calc1(root,root);
        up[root]=root;
        pre_calc2(root,root);
        dfs(root,root);
        int cnt=0;
        while(cnt++<k){
            int beg=*rest.begin();
            take.insert(beg);
            rest.erase(rest.find(beg));
        }
        int ans=0;
        for(int it:take){
            ans+=it;
        }
        cout<<ans<<nl;
    }
}

/**
11 3
1 2 5
2 3 3
2 6 5
3 4 4
3 5 2
1 7 6
7 8 4
7 9 5
1 10 1
10 11 1
**/

int32_t main(){
    ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

    int t=1;
//    cin>>t;
    while(t--){
        solve();
    }
}

• Subtask 1: 8 / 8
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 0 / 20
• Subtask 5: 0 / 12
• Subtask 6: 0 / 32