430C codeforces - Xor-Tree

430C codeforces - Xor-Tree

Link ; http://codeforces.com/problemset/problem/430/C

Solution in C++

#include <bits/stdc++.h>

using namespace std;

int n,sol,t1,t2;

vector<int> bas(100005),goal(100005);

vector<int> adj[100005],solu;

int viz[100005];

int nn[2];

void dfs(int x,int rem)

{

    int lol=0;

    if(viz[x])return;

        viz[x]=1;

    if(nn[rem%2]%2)bas[x]=(bas[x]+1)%2;

    if(bas[x]!=goal[x])nn[rem%2]++,

        sol++,bas[x]=(bas[x]+1)%2,

        solu.push_back(x),lol=1;

    for(auto u : adj[x])dfs(u, (rem+1)%2 );

    if(lol)nn[rem%2]--;

}

int main()

{

    ios::sync_with_stdio(0);

    cin.tie(0);cout.tie(0);

    cin>>n;

    for(int i=0;i<n-1&& cin>>t1>>t2;i++)

        adj[t1].push_back(t2),

        adj[t2].push_back(t1);

    for(int i=1;i<=n;i++)cin>>bas[i];

    for(int i=1;i<=n;i++)cin>>goal[i];

    dfs(1,0);

    cout<<sol<<"\n";

    for(auto u : solu)cout<<u<<"\n";

    return 0;

}

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About Mohamed Sobhi

My name is Mo.Sobhy ,I study at School excelling high school in Ain Shams ,Cairo
My hobbies is programming ,and web development ,playing chess and writing horror stories.