I have written the following code for the problem Linova and Kingdom I am getting a WA on some test case. I am unable to identify the error. Please help me out.

include <bits/stdc++.h>

define ll long long

define pb push_back

using namespace std; vector vec[200006],contri(200006,0),sub(200006,1); void solve(ll node, ll parent, ll level) { int cnt=0; for(auto it:vec[node]) { if(it!=parent) { solve(it,node,level+1); cnt+=sub[it]; } } sub[node]+=cnt; contri[node] = level-sub[node]; } int main() { ll n,k; cin>>n>>k; for(ll i=0;i<n-1;i++) { ll u,v; cin>>u>>v; vec[v].pb(u); vec[u].pb(v); } solve(1,0,1); sort(contri.begin(),contri.end(),greater()); ll ans=0; for(ll i=0;i<k;i++) { ans+=contri[i]; } cout<<ans; }

Thanks in advance