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- //Tanisha Pareek.
- // a=97, z=122, A=65, Z=90, '0'-48, '9'-57
- #include <bits/stdc++.h>
- #include<ext/pb_ds/assoc_container.hpp>
- #include<ext/pb_ds/tree_policy.hpp>
- using namespace __gnu_pbds;
- using namespace std;
- #define pb push_back
- typedef long long ll;
- typedef vector<ll> vll;
- typedef tree<ll, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> pbds; // find_by_order(k)--(returns iterator of ele. at index k), order_of_key(k)--(returns index of k if k was present in set.)
- typedef tree<ll, null_type, less_equal<int>, rb_tree_tag,tree_order_statistics_node_update> multipbds;
- //--CONSTANTS--
- const ll mod = 1e9 + 7;
- //--USEFUL FUNCTIONS--
- bool isPalindrome(string str){ll low = 0,high = str.length() - 1;while (low < high){if (str[low] != str[high])return false;low++,high--;}return true;}
- bool isPrime(ll n){for(ll i=2;(i*i)<=n;i++){if((n%i) == 0) return false;}return true;}
- ll highestSmallerPower(ll num, ll p){ll cnt=0,curr=1;while((curr*p)<=num) curr*=p,cnt++;return cnt;} // gives largest power value(say x) such that p^x <= num
- ll binpow(ll num, ll p){ll ans=1;while(p>0){if(p&1) ans = ans*num;num = num*num;p/=2;}return ans;} // num^p
- ll modulerExpo(ll num,ll p,ll m){ll ans=1;num%=m;while(p){if(p&1) ans*=num;ans%=m;p = p>>1;num*=num;num%=m;}return ans;} // (num^p)%m
- ll phin(ll n){ll result = n;for(ll i=2;(i*i)<=n;i++){if(n%i == 0){while(n%i == 0) n/=i;result -= result/i;}}if(n>1) result -= (result/n);return result;}
- // To find if two elements are from same component, just check their parent using dsu.
- // To find no. of connected components, run a loop on all elements and find their parents. Maintain count of unique parents, that's the answer
- // Loop exists when two elements are already in the same component and you are performing their union.
- struct DSU {
- vll parent,sizz;
- DSU() {}
- DSU(ll n) {
- for(ll i=0;i<=n;i++) parent.push_back(i);
- sizz.assign(n+1,1);
- }
- ll find_set(ll v) {
- if(parent[v] == v) return v;
- return parent[v] = find_set(parent[v]);
- }
- void union_set(ll u,ll v) {
- u = find_set(u);
- v = find_set(v);
- if(v == u) return;
- if(sizz[u] > sizz[v]) swap(u,v);
- parent[u] = v;
- sizz[v] += sizz[u];
- }
- };
- // ---- Solution ----
- ll cal(vll &childs, map<ll,vll> &tree, vll &visited, ll root)
- {
- visited[root]=1;
- for(auto i:tree[root])
- {
- if(visited[i] == 1) continue;
- childs[root] += (1+cal(childs,tree,visited,i));
- }
- return childs[root];
- }
- int main()
- {
- #ifndef ONLINE_JUDGE
- freopen("input.txt", "r", stdin);
- freopen("output.txt", "w", stdout);
- #endif
- ios_base::sync_with_stdio(false);
- cin.tie(0);
- cout.tie(0);
- ll t;
- cin>>t;
- while(t--)
- {
- ll n;
- cin>>n;
- map<ll,vll> tree;
- ll ui,vi;
- for(ll i=0;i<(n-1);i++)
- {
- cin>>ui>>vi;
- // if(ui>vi) swap(ui,vi);
- tree[ui].pb(vi);
- tree[vi].pb(ui);
- }
- vll childs((n+1),0);
- vll visited((n+1),0);
- visited[0]=1;
- cal(childs,tree,visited,1);
- // for(auto i:tree)
- // {
- // cout<<"i:"<<i.first<<": ";
- // for(auto x:i.second) cout<<x<<" ";
- // cout<<"\n";
- // }
- // for(ll i=1;i<=n;i++) cout<<"i:"<<i<<" -> "<<childs[i]<<"\n";
- ll ans=0;
- ll root = 1,par=-1;
- while(1)
- {
- if(tree[root].size() == 1)
- {
- if(childs[root] == 0) break;
- ans += (childs[root]-1);
- break;
- }
- else if(tree[root].size()==2)
- {
- ll val1 = tree[root][0];
- ll val2 = tree[root][1];
- if(val1 == par)
- {
- ans += childs[val2];
- break;
- }
- else if(val2 == par)
- {
- ans += childs[val1];
- break;
- }
- else
- {
- par=root;
- if(childs[val1] > childs[val2])
- {
- ans += childs[val1];
- root = val2;
- }
- else
- {
- ans += childs[val2];
- root = val1;
- }
- }
- }
- else
- {
- ll val1 = tree[root][0];
- ll val2 = tree[root][1];
- if(val1 == par) val1 = tree[root][2];
- else if(val2 == par) val2 = tree[root][2];
- par=root;
- if(childs[val1] > childs[val2])
- {
- ans += childs[val1];
- root = val2;
- }
- else
- {
- ans += childs[val2];
- root = val1;
- }
- }
- }
- cout<<ans<<"\n";
- }
- return 0;
- }
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