Submission #484295

#	Time	Username	Problem	Language	Result	Execution time	Memory
484295		urosk	Election Campaign (JOI15_election_campaign)	C++14	100 / 100	434 ms	138648 KiB

election_campaign

// __builtin_popcount(x) broj bitova
// __builtin_popcountll(x) long long
#include "bits/stdc++.h"
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#define ld double
#define ll long long
#define ull unsigned long long
#define llinf 100000000000000000LL // 10^17
#define iinf 2000000000 // 2*10^9
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define sz(a) int(a.size())
#define all(a) a.begin(),a.end()
#define rall(a) a.begin(),a.end(),greater<int>()
#define getunique(v) {sort(all(v)); v.erase(unique(all(v)), v.end());}
#define pi 3.14159265358979323846
#define here cerr<<"---------------------------\n"
#define ceri(a,l,r) {for(ll i = l;i<=r;i++) cerr<<a[i]<< " ";cerr<<endl;}
#define yes cout<<"YES"<<endl
#define no cout<<"NO"<<endl
using namespace std;
using namespace __gnu_pbds;

typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

void setIO(string inoutname)
{
	freopen((inoutname+".in").c_str(),"r",stdin);
    	freopen((inoutname+".out").c_str(),"w",stdout);
}
#define mod 1
ll gcd(ll a, ll b)
{
   if(b==0) return a;
   if(a==0) return b;
   if(a>=b)  return gcd(a%b,b);
   return  gcd(a,b%a);
}
ll lcm(ll a,ll b){
   return (a/gcd(a,b))*b;
}
ll add(ll a,ll b){
	a+=b;
	a+=mod;
	if(a>=mod) a%=mod;
	return a;
}
ll mul(ll a,ll b){return(a*b)%mod;}
#define maxn 1000005
#define lg 25
ll n,m;
vector<ll> g[maxn];
vector<ll> a[maxn],b[maxn],c[maxn];
ll t[4*maxn];
ll st[maxn][lg];
ll in[maxn],out[maxn];
ll dp[maxn];
ll ti = 0;
void dfs(ll u,ll par){
    in[u] = ++ti; st[u][0] = par;
    for(ll s : g[u]) if(s!=par) dfs(s,u);
    out[u] = ++ti;
}
void init_lca(){for(ll j = 1;j<lg;j++) for(ll i = 1;i<=n;i++) st[i][j] = st[st[i][j-1]][j-1];}
bool in_t(ll v,ll u){return in[u]<=in[v]&&out[u]>=out[v];}
ll lca(ll v,ll u){
    if(in_t(v,u)) return u;
    if(in_t(u,v)) return v;
    for(ll j = lg-1;j>=0;j--) if(!in_t(v,st[u][j])) u = st[u][j];
    return st[u][0];
}
void upd(ll v,ll tl,ll tr,ll i,ll x){
    if(tl==tr){
        t[v]+=x;
        return;
    }
    ll mid = (tl+tr)/2;
    if(i<=mid) upd(2*v,tl,mid,i,x);
    else upd(2*v+1,mid+1,tr,i,x);
    t[v] = t[2*v] + t[2*v+1];
}
ll get(ll v,ll tl,ll tr,ll l,ll r){
    if(l>r) return 0;
    if(tl==l&&tr==r) return t[v];
    ll mid = (tl+tr)/2;
    return get(2*v,tl,mid,l,min(mid,r)) + get(2*v+1,mid+1,tr,max(l,mid+1),r);
}
void reshi(ll u,ll par){
    for(ll s : g[u]) if(s!=par) reshi(s,u);
    ll x = get(1,1,ti,in[u],in[u]);
    dp[u] = x;
    for(ll i = 0;i<sz(a[u]);i++) dp[u] = max(dp[u],get(1,1,ti,in[u],in[a[u][i]])+get(1,1,ti,in[u],in[b[u][i]])+c[u][i]-x);
    upd(1,1,ti,in[par],dp[u]);
    upd(1,1,ti,in[u],-dp[u]);
    upd(1,1,ti,out[par],-dp[u]);
    upd(1,1,ti,out[u],dp[u]);
}
void tc(){
	ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);
    cin >> n;
    for(ll i = 1;i<=n-1;i++){
        ll x,y; cin >> x >> y;
        g[x].pb(y);
        g[y].pb(x);
    }
    dfs(1,1);
    init_lca();
    cin >> m;
    for(ll i = 1;i<=m;i++){
        ll ai,bi,ci;
        cin >> ai >> bi >> ci;
        ll x = lca(ai,bi);
        a[x].pb(ai);
        b[x].pb(bi);
        c[x].pb(ci);
    }
    reshi(1,1);
    cout<<dp[1]<<endl;
}
int main(){
	ios_base::sync_with_stdio(false);cerr.tie(0);cout.tie(0);cin.tie(0);
	//setIO("lol");
	int t; t = 1;
	while(t--){
		tc();
	}
	return 0;
}

Compilation message (stderr)

election_campaign.cpp: In function 'void setIO(std::string)':
election_campaign.cpp:35:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   35 |  freopen((inoutname+".in").c_str(),"r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
election_campaign.cpp:36:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |      freopen((inoutname+".out").c_str(),"w",stdout);
      |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 30 / 30
• Subtask 5: 10 / 10
• Subtask 6: 40 / 40