Submission #203706

#	Time	Username	Problem	Language	Result	Execution time	Memory
203706		thebes	Beads and wires (APIO14_beads)	C++14	0 / 100	7 ms	4984 KiB

beads

#include <bits/stdc++.h>
#define DEBUG 1
using namespace std;

namespace output{
    void __(short x){cout<<x;}
    void __(unsigned x){cout<<x;}
    void __(int x){cout<<x;}
    void __(long long x){cout<<x;}
    void __(unsigned long long x){cout<<x;}
    void __(double x){cout<<x;}
    void __(long double x){cout<<x;}
    void __(char x){cout<<x;}
    void __(const char*x){cout<<x;}
    void __(const string&x){cout<<x;}
    void __(bool x){cout<<(x?"true":"false");}
    template<class S,class T>
    void __(const pair<S,T>&x){__(DEBUG?"(":""),__(x.first),__(DEBUG?", ":" "),__(x.second),__(DEBUG?")":"");}
    template<class T>
    void __(const vector<T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    template<class T>
    void __(const set<T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    template<class T>
    void __(const multiset<T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    template<class S,class T>
    void __(const map<S,T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    void pr(){cout<<"\n";}
    template<class S,class... T>
    void pr(const S&a,const T&...b){__(a);if(sizeof...(b))__(' ');pr(b...);}
}

using namespace output;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<double,double> pdd;
typedef pair<ld,ld> pld;
typedef vector<int> vi;
typedef vector<ll> vl;

#define pb push_back
#define fox(i,x,y) for(int i=(x);i<=(y);i++)
#define foxr(i,x,y) for(int i=(y);i>=(x);i--)

const int MN = 2e5+5;
int dp[MN][2], N, i, x, y, w;
vector<pii> adj[MN];

void solve(int n,int p){
    vi arr; int w = 0;
    for(auto v : adj[n]){
        if(v.first == p){
            w = v.second;
            continue;
        }
        solve(v.first, n);
        dp[n][0] += max(dp[v.first][0],dp[v.first][1]);
        int c = dp[v.first][0]-max(dp[v.first][1],dp[v.first][0])+v.second;
        arr.pb(c);
    }
    sort(arr.begin(),arr.end(),[](int i,int j){return i>j;});
    if(arr.size()>=2){
        dp[n][0]+=max(0,arr[0]+arr[1]);
    }
    if(arr.size()>=1&&p){
        dp[n][1]+=max(0,arr[0]+w);
    }
}

int main(){
    for(scanf("%d",&N),i=1;i<N;i++){
        scanf("%d%d%d",&x,&y,&w);
        adj[x].pb({y,w});
        adj[y].pb({x,w});
    }
    solve(1,0);
    printf("%d\n",dp[1][0]);
    return 0;
}

Compilation message (stderr)

beads.cpp: In function 'int main()':
beads.cpp:73:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(scanf("%d",&N),i=1;i<N;i++){
         ~~~~~~~~~~~~~~^~~~
beads.cpp:74:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d%d",&x,&y,&w);
         ~~~~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 13
• Subtask 2: 0 / 15
• Subtask 3: 0 / 29
• Subtask 4: 0 / 43