Coding/E_1_Weights_Division_easy_version.cpp at main · nishantlamba29/Coding · GitHub

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#include <bits/stdc++.h>
using namespace std;
#define int long long

const int N = 1e5 + 5;
vector<pair<int, int>> adj[N];
int weight[N];
int dp[N];

int dfs(int node, int p) {
    bool leaf = 1;
    int ans = 0;
    for(auto &j : adj[node]) if(j.first != p) {
        leaf = 0;
        int cnt = dfs(j.first, node);
        ans += cnt;
        dp[j.second] += cnt;
    }

    return ans + leaf;
}

void solve() {
    int n, S;
    cin >> n >> S;

    for(int i=0;i<=n;i++) {
        adj[i].clear();
        dp[i] = 0;
    }

    for(int i=0;i<n-1;i++) {
        int u, v, w;
        cin >> u >> v >> weight[i];
        adj[u].push_back({v, i});
        adj[v].push_back({u, i});
    }

    dfs(1, -1);

    set<pair<int, int>, greater<pair<int, int>>> st;
    vector<int> wt(n-1);
    for(int i=0;i<n-1;i++) {
        wt[i] = weight[i];
    }
    int curr = 0;
    for(int i=0;i<n-1;i++) {
        st.insert({dp[i] * (wt[i] - (wt[i] / 2)), i});
        curr += dp[i] * wt[i];
    }

    int ans = 0;
    while(!st.empty() && curr > S) {

        auto it = st.begin();
        int sum = it->first;
        int id = it->second;
        st.erase(it);
        curr -= sum;
        ans++;
        wt[id] /= 2;
        st.insert({dp[id] * (wt[id] - (wt[id] / 2)), id});

    }

    cout << ans << "\n";

}


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

    int _;
    cin >> _;
    while (_-->0) {
        solve();
    }

    return 0;
}