Submission #1247851

#	Time	Username	Problem	Language	Result	Execution time	Memory
1247851		tralalero_tralala	Power Plant (JOI20_power)	C++20	100 / 100	159 ms	27240 KiB

power

#include <bits/stdc++.h>
#define _ ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define fore(i,a,b) for(lli i = (a), abcdxd = (b); i < abcdxd; i++)
#define f first
#define s second
#define pb push_back
#define ENDL '\n'
#define sz(s) lli((s).size())
#define all(v) (v).begin(), (v).end()
#define rall(v) (v).rbegin(), (v).rend()
using namespace std;
typedef long long lli;
typedef pair<lli,lli> ii;
typedef vector<lli> vi;
typedef vector<ii> vii;
typedef long double ld;
#define deb(x) cout << #x << ": " << x << endl;

const lli N = 2e5 + 12;

lli n;
lli ans = 0;

vi adj[N];
char v[N];

lli calc(lli u, lli p = -1){
  lli res = 0, cc = 0, mx = 0;
  for (auto & i : adj[u]) if (i != p){
    lli xx = calc(i, u);
    if (xx > 0) cc++;
    res += xx;
    mx = max(mx, xx);
  }
  if (v[u] == '1'){
    ans = max({ans, res + (cc > 1 ? -1 : 1), mx + 1});
  }
  res = max(lli(v[u] - '0'), res - lli(v[u] - '0'));
  return res;
}

void solve(){
  cin >> n;
  fore(i,1,n){
    lli a, b; cin >> a >> b; a--, b--;
    adj[a].pb(b);
    adj[b].pb(a);
  }
  fore(i,0,n) cin >> v[i];
  fore(i,0,n) if (v[i] == '1'){
    calc(i);
    cout << ans << endl;
    exit(0);
  }
  cout << 0 << endl;
}
 
int main(){ _
  // freopen("tracing.in", "r", stdin);
  // freopen("tracing.out", "w", stdout);
  // lli t; cin >> t;
  // while (t--)
    solve();
  return 0;
}

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