/* Aa^~ kokoro ga pyonpyon suru n jaa^~
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// MMMMM#<<_jwr:(Z4QHHMMHMHHHHHHHHHHHHHHHHHHHHHHHHHHHH###NHSXZ>` ~````.OXtt>~._<?MM
*/
#include<bits/stdc++.h>
using namespace std;
#ifndef ONLINE_JUDGE
#define dbg(x...) do { cout << "\033[32;1m " << #x << " -> "; err(x); } while (0)
void err() { cout << "\033[39;0m" << endl; }
template<template<typename...> class T, typename t, typename... A>
void err(T<t> a, A... x) { for (auto v: a) cout << v << ' '; err(x...); }
template<typename T, typename... A>
void err(T a, A... x) { cout << a << ' '; err(x...); }
#else
#define dbg(...)
#endif
typedef long long ll;
typedef pair<int,int> pi;
typedef vector<int> vi;
template<class T> using vc=vector<T>;
template<class T> using vvc=vc<vc<T>>;
template<class T> void mkuni(vector<T>&v)
{
    sort(v.begin(),v.end());
    v.erase(unique(v.begin(),v.end()),v.end());
}
ll rand_int(ll l, ll r) //[l, r]
{
    static mt19937_64 gen(chrono::steady_clock::now().time_since_epoch().count());
    return uniform_int_distribution<ll>(l, r)(gen);
}
template<class T>
void print(T x,int suc=1)
{
    cout<<x;
    if(suc==1) cout<<'\n';
    else cout<<' ';
}
template<class T>
void print(const vector<T>&v,int suc=1)
{
    for(int i=0;i<v.size();i++)
    print(v[i],i==(int)(v.size())-1?suc:2);
}
const int maxn=1e5+7;
int fa[maxn];
int sz[maxn];
struct Edge{
    int to,id;
};
void init()
{
    for(int i=0;i<maxn;i++) fa[i]=i;
}
int Find(int x)
{
    return x==fa[x]?x:fa[x]=Find(fa[x]);
}
vi ans;
vc<Edge> G[maxn];
void Union(int x,int y,int id)
{
    int xx=x,yy=y;
    x=Find(x),y=Find(y);
    if(x!=y)
    {
        sz[x]+=sz[y];
        fa[y]=x;
        //dbg(xx,yy,id);
        G[xx].push_back(Edge{yy,id});
        G[yy].push_back(Edge{xx,id});
    }
}
bool vis[maxn];
vc<pi> p;
void dfs(int u)
{
    vis[u]=1;
    sz[u]=p[u].second^(u?p[u-1].second:0);
    for(auto &e:G[u])
    {
        int v=e.to;
        if(!vis[v])
        {
            dfs(v);
            sz[u]+=sz[v];
            if(sz[v]&1) ans.push_back(e.id);
        }
    }
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n,m;
    cin>>n>>m;
    vi all;
    p=vc<pi>(n);
    for(int i=0;i<n;i++)
    {
        cin>>p[i].first>>p[i].second;
        all.push_back(p[i].first);
    }
    sort(p.begin(),p.end());
    sort(all.begin(),all.end());
    auto getid=[&](int x){
        return lower_bound(all.begin(),all.end(),x)-all.begin();
    };
    init();
    for(int i=0;i<n;i++)
        sz[i]=p[i].second^(i?p[i-1].second:0);
    for(int i=0;i<m;i++)
    {
        int l,r;
        cin>>l>>r;
        l=getid(l);
        r=getid(r+1);
        if(l!=r)
            Union(l,r,i+1);
    }
    bool ok=1;
    for(int i=0;i<=n;i++)
    {
        if(Find(i)==i)
        {
            if(Find(n)==i)
            {
                if(sz[i]&1) p[n].second=p[n-1].second^1;
                continue;
            }
            if(sz[i]&1) ok=0;
        }
    }
    if(!ok) cout<<"-1\n";
    else{
        for(int i=0;i<=n;i++)
        {
            if(p[i].second&&!vis[i])
                dfs(i);
        }
        sort(ans.begin(),ans.end());
        print(ans.size());
        print(ans);
    }
}

Measured memory_bytes: 9080