#include "simurgh.h"
#pragma GCC optimize("Ofast,unroll-loops")
#include<bits/stdc++.h>
//#define int long long
#define ll long long
#define down cout<<'\n';
#define debug cout<<" cucuucucuuu",down
#define modwwe int t;cin>>t; while(t--)
#define bit(i,j) (i>>j&1)
#define sobit(a) __builtin_popcountll(a)
#define task2 "ftree"
#define task "test"
#define fin(x) freopen(x".inp","r",stdin)
#define fou(x) freopen(x".out","w",stdout)
#define pb push_back
#define mask(k) (1ll<<k)
#define checktime cerr << (double)clock() / CLOCKS_PER_SEC * 1000 << " ms";
using namespace std;
#define getchar_unlocked getchar
mt19937 rd(chrono::steady_clock::now().time_since_epoch().count());
int rand(int l,int r)
{
return uniform_int_distribution<int>(l,r)(rd);
}
void phongbeo();
const int inf = 4e18+1;
const int mod2 = 1e9+7;
//const int base=67;
int n, m, s1, s2, s4, s3, sf, k, s5, s6, mx, s7, s8, s9, mx2, res, dem2 = 0, dem = 0, s33, dem3, dem4, mid, l2, r2, center;
int i, s10, s12,k1,k2,k3,s11,lim,w,l,r,dem5,dem6,dem7,dem9,now,root,q,start,en;
int kk;
int el = 19;/*
main()
{
if(fopen(task2".inp","r"))
{
fin(task2);
fou(task2);
}
if(fopen(task".inp","r"))
{
fin(task);
fou(task);
}
ios_base::sync_with_stdio(0);
cout.tie(0);
cin.tie(0);
// cin>>s1;
// int t;cin>>t;while(t--)
phongbeo(),down
checktime
}*/
vector<int> U,V;
int d[501][501];
struct ib
{
int a,b;
};
struct dsuconcu
{
ib dsu[501];
void reset(int n)
{
for(int i=0; i<=n; i++)
dsu[i]= {1,i};
}
int get(int x)
{
if(dsu[x].b!=x)dsu[x].b=get(dsu[x].b);
return dsu[x].b;
}
bool noi(int x,int y)
{
x=get(x);
y=get(y);
if(x==y) return 0;
if(dsu[x].a<dsu[y].a)swap(x,y);
dsu[x].a+=dsu[y].a;
dsu[y].b=x;
return 1;
}
};/*
namespace jury
{
dsuconcu ds;
void wrong(int x)
{
cout<<"WRONG "<<x;
exit(0);
}
void check_spanning_tree(vector<int>&v)
{
ds.reset(n);
int s=0;
for(int i=0; i<v.size(); i++)
s+=ds.noi(U[v[i]],V[v[i]]);
if(s!=v.size())wrong(4);
}
int count_common_roads(vector<int>&v)
{
if(v.size()!=n-1) wrong(1);
for(int i=0; i<v.size(); i++)
{
for(int j=i+1; j<v.size(); j++)
if(v[i]==v[j])
{
wrong(2);
}
if(v[i]>=m||v[i]<0)wrong(3);
}
check_spanning_tree(v);
int s=0;
for(int i=0; i<v.size(); i++)
s+=d[U[v[i]]][V[v[i]]];
return s;
}
};*/
namespace phongcubu
{
dsuconcu ds;
vector<int> enemy,ke[501],all[501];
int base;
ib edge[130001],a[501];
int cost[501];
int c[501][501],pos[501][501],real[130001],royal[501],par[501];
bool go[501];
int dd[501];/*
int count_common_roads(vector<int>&v)
{
return jury::count_common_roads(v);
}*/
void dfs(int x)
{
go[x]=1;
dd[x]=++dem3;
for(auto f:ke[x])
if(!go[f])
{
par[f]=x;
c[f][x]=c[x][f]=enemy.size();
enemy.pb(pos[x][f]);
dfs(f);
}
else if(par[x]!=f)
{
if(dd[f]<dd[x])
{
if(x<f)all[x].pb(f);
else all[f].pb(x);
s2=x;
while(s2!=f)
{
if(a[s2].a==-1)a[s2]= {x,f};
s2=par[s2];
}
}
}
}
int get(int x,int y,int z)
{
int pc=c[x][par[x]];
enemy[pc]=pos[y][z];
int ans=count_common_roads(enemy);
enemy[pc]=pos[x][par[x]];
return ans;
}
void work(int x)
{
s2=a[x].a;
s3=a[x].b;
vector<int> ask;
while(s2!=s3)
{
ask.pb(s2);
s2=par[s2];
}
s2=-1;
s3=-1;
for(auto f:ask)
if(royal[f]!=-1)
{
s2=get(f,a[x].a,a[x].b);
s3=royal[f];
break;
}
if(s3!=-1)
{
for(auto f:ask)
if(royal[f]==-1)
{
s4=get(f,a[x].a,a[x].b);
if(s4==s2)royal[f]=s3;
else royal[f]=1-s3;
}
}
else
{
s2=base;
for(auto f:ask)
cost[f]=get(f,a[x].a,a[x].b),s2=max(s2,cost[f]);
for(auto f:ask)
{
if(cost[f]==s2)royal[f]=0;
else royal[f]=1;
}
}
}
bool check(vector<int> v)
{
ds.reset(n);
for(auto x:v)
if(!ds.noi(edge[x].a,edge[x].b))
{
///wtf
assert(0);
}
int s=0;
for(auto x:enemy)
if(ds.noi(edge[x].a,edge[x].b))
{
v.pb(x);
if(par[edge[x].a]==edge[x].b)s+=royal[edge[x].a];
else s+=royal[edge[x].b];
}
return s-count_common_roads(v)<0;
}
vector<int> find_roads(int N,vector<int> U,vector<int> V)
{
n=N;
m=U.size();
enemy.clear();
for(int i=0; i<n; i++)
ke[i].clear(),a[i]= {-1,-1},go[i]=0;
for(int i=0; i<m; i++)
real[i]=0;
for(int i=0; i<m; i++)
{
edge[i]= {U[i],V[i]};
ke[U[i]].pb(V[i]),
ke[V[i]].pb(U[i]);
}
for(int i=0; i<m; i++)
pos[U[i]][V[i]]=pos[V[i]][U[i]]=i;
dfs(0);
base=count_common_roads(enemy);
/// if a[i]==-1 no bridge
for(int i=1; i<n; i++)
if(a[i].a==-1)royal[i]=1;
else royal[i]=-1; /// dont know
for(int i=1; i<n; i++)
{
if(royal[i]==-1)
work(i);
real[pos[i][par[i]]]=royal[i];
}
for(int i=0; i<n; i++)
{
r=-1;
while(true)
{
s9=r+1;
l=r+1;
r=all[i].size()-1;
while(l<=r)
{
int mid=l+r>>1;
vector<int> dec;
for(int j=s9; j<=mid; j++)
dec.pb(pos[i][all[i][j]]);
if(check(dec))r=mid-1;
else l=mid+1;
}
if(r==all[i].size()-1) break;
r++;
real[pos[i][all[i][r]]]=1;
}
}
vector<int> haha;
for(int i=0; i<m; i++)
if(real[i])
haha.pb(i);
return haha;
}
};
vector<int> find_roads(int N,vector<int> U,vector<int> V)
{
return phongcubu::find_roads(N,U,V);
}
void phongbeo()
{
cin>>n>>m;
for(int i=1; i<=m; i++)
{
cin>>l>>r;
U.pb(l);
V.pb(r);
}
for(int i=1; i<n; i++)
{
cin>>l;
d[U[l]][V[l]]=1;
}
find_roads(n,U,V);
}
