Submission #734128

#	Time	Username	Problem	Language	Result	Execution time	Memory
734128		n0sk1ll	Power Plant (JOI20_power)	C++17	100 / 100	152 ms	31764 KiB

power

#include <bits/stdc++.h>

#define FAST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);cerr.tie(0)
#define mp make_pair
#define xx first
#define yy second
#define pb push_back
#define pf push_front
#define popb pop_back
#define popf pop_front
#define all(x) x.begin(),x.end()
#define ff(i,a,b) for (int i = a; i < b; i++)
#define fff(i,a,b) for (int i = a; i <= b; i++)
#define bff(i,a,b) for (int i = b-1; i >= a; i--)
#define bfff(i,a,b) for (int i = b; i >= a; i--)

using namespace std;
long double typedef ld;
unsigned int typedef ui;
long long int typedef li;
pair<int,int> typedef pii;
pair<li,li> typedef pli;
pair<ld,ld> typedef pld;
vector<vector<int>> typedef graph;
unsigned long long int typedef ull;
//const int mod = 998244353;
const int mod = 1000000007;







//Note to self: Check for overflow

graph g(200005);
bool struja[200005];
int dp[200005];
int ans=0;

void dfs(int p, int q)
{
    int suma=0,mx=0;
    for (auto it : g[p]) if (it!=q)
    {
        dfs(it,p);
        suma+=dp[it];
        mx=max(mx,dp[it]);
    }

    ans=max(ans,mx+struja[p]);
    dp[p]=max(dp[p],suma-struja[p]);
    if (struja[p]) dp[p]=max(dp[p],1);
    ans=max(ans,dp[p]);
}

int main()
{
    FAST;

    int n; cin>>n;
    ff(i,1,n)
    {
        int u,v; cin>>u>>v;
        g[u].pb(v),g[v].pb(u);
    }

    string s; cin>>s;
    fff(i,1,n) struja[i]=(s[i-1]=='1');

    dfs(1,0);
    cout<<ans<<"\n";

    //fff(i,1,n) cout<<i<<": "<<dp[i]<<endl;
}

//Note to self: Check for overflow

• Subtask 1: 6 / 6
• Subtask 2: 41 / 41
• Subtask 3: 53 / 53