#include <bits/stdc++.h>
#include <boost/multiprecision/cpp_int.hpp>
#include <boost/multiprecision/cpp_dec_float.hpp>
using namespace std;
#ifdef LOCAL_DEV
	void debug_impl() { std::cerr << std::endl; }
	template<typename Head, typename... Tail> void debug_impl(Head head, Tail... tail) { std::cerr << " " << head << (sizeof...(tail) ? "," : ""); debug_impl(tail...); }
	#define debug(...) std::cerr << std::boolalpha << "(" << #__VA_ARGS__ << ") ="; debug_impl(__VA_ARGS__); std::cerr << std::noboolalpha;
#else
	#define debug(...)
#endif
#ifdef LOCAL_TEST
	#define BOOST_STACKTRACE_USE_ADDR2LINE
	#define BOOST_STACKTRACE_ADDR2LINE_LOCATION /usr/local/opt/binutils/bin/addr2line
	#define _GNU_SOURCE
	#include <boost/stacktrace.hpp>
	template<typename T> class dvector : public std::vector<T> {
	public:
		dvector() : std::vector<T>() {}
		explicit dvector(size_t n, const T& value = T()) : std::vector<T>(n, value) {}
		dvector(const std::vector<T>& v) : std::vector<T>(v) {}
		dvector(const std::initializer_list<T> il) : std::vector<T>(il) {}
		dvector(const typename std::vector<T>::iterator first, const typename std::vector<T>::iterator last) : std::vector<T>(first, last) {}
		dvector(const std::string::iterator first, const std::string::iterator last) : std::vector<T>(first, last) {}
		T& operator[](size_t n) {
			try { return this->at(n); } catch (const std::exception& e) {
				std::cerr << boost::stacktrace::stacktrace() << std::endl; return this->at(n);
			}
		}
		const T& operator[](size_t n) const {
			try { return this->at(n); } catch (const std::exception& e) {
				std::cerr << boost::stacktrace::stacktrace() << std::endl; return this->at(n);
			}
		}
	};
	class dbool {
	private:
		bool boolvalue;
	public:
		dbool() : boolvalue(false) {}
		dbool(bool b) : boolvalue(b) {}
		dbool(const dbool &b) : boolvalue(b.boolvalue) {}
		operator bool&() { return boolvalue; }
		operator const bool&() const { return boolvalue; }
	};
	template<typename T1, typename T2> std::ostream& operator<<(std::ostream& s, const std::pair<T1, T2>& p) { return s << "(" << p.first << ", " << p.second << ")"; }
	template<typename T> std::ostream& operator<<(std::ostream& s, const dvector<T>& v) {
		for (int i = 0, len = v.size(); i < len; ++i){ s << v[i]; if (i < len - 1) s << "\t"; } return s; }
	template<typename T> std::ostream& operator<<(std::ostream& s, const dvector< dvector<T> >& vv) {
		for (int i = 0, len = vv.size(); i < len; ++i){ s << vv[i] << std::endl; } return s; }
	template<typename T1, typename T2> std::ostream& operator<<(std::ostream& s, const std::map<T1, T2>& m) {
		s << "{" << std::endl; for (auto itr = m.begin(); itr != m.end(); ++itr){ s << "\t" << (*itr).first << " : " << (*itr).second << std::endl; } s << "}" << std::endl; return s; }
	template<typename T> std::ostream& operator<<(std::ostream& s, const std::set<T>& se) {
		s << "{ "; for (auto itr = se.begin(); itr != se.end(); ++itr){ s << (*itr) << "\t"; } s << "}" << std::endl; return s; }
	template<typename T> std::ostream& operator<<(std::ostream& s, const std::multiset<T>& se) {
		s << "{ "; for (auto itr = se.begin(); itr != se.end(); ++itr){ s << (*itr) << "\t"; } s << "}" << std::endl; return s; }
	#define vector dvector
	#define bool dbool
#endif
//#define int long long
using ll = long long;
using bll = boost::multiprecision::cpp_int;
using bdouble = boost::multiprecision::cpp_dec_float_100;
//constexpr int INF = 1e9;//INT_MAX=(1<<31)-1=2147483647
constexpr ll INF = (ll)1e18;//(1LL<<63)-1=9223372036854775807
constexpr ll MOD = (ll)1e9 + 7;
constexpr double EPS = 1e-9;
constexpr int dx[4]={1,0,-1,0};
constexpr int dy[4]={0,1,0,-1};
#define p(var) std::cout<<var<<std::endl
#define PI (acos(-1))
#define rep(i, n)   for(ll i=0, i##_length=(n); i< i##_length; ++i)
#define repeq(i, n) for(ll i=1, i##_length=(n); i<=i##_length; ++i)
#define all(v) (v).begin(), (v).end()
#define uniq(v) (v).erase(unique((v).begin(), (v).end()), (v).end());
template<typename T> inline void pv(vector<T> &v) { for(ll i=0, N=v.size(); i<N; i++) std::cout << v[i] << " \n"[i==N-1]; }
template<typename T> inline T gcd(T a, T b) { return b ? gcd(b,a%b) : a; }
template<typename T> inline T lcm(T a, T b) { return a / gcd(a,  b) * b; }
template<typename T1, typename T2> inline T1 power(T1 x, T2 n){ return n ? power(x*x%MOD,n/2)*(n%2?x:1)%MOD : 1; }
template<typename T1, typename T2> inline bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }
template<typename T1, typename T2> inline bool chmin(T1 &a, T2 b) { return a > b && (a = b, true); }

/*-----8<-----8<-----*/


class Edge {
public:
	ll from,to,cost;
	Edge() {}
	Edge(ll from, ll to, ll cost) : from(from), to(to), cost(cost) {}
};
ostream& operator<<(ostream& s, const Edge& e) {
	s << "{ " << e.from << " -> " << e.to << ", " << e.cost << " }";
	return s;
}

/*
引数
　g:探索するグラフ
　start:この点を根とする全域木を求める
戻り値
　return:最小全域木を構成する辺のコストの総和
　ming:最小全域木のグラフ
*/
ll prim(const vector<vector<Edge>> &g, vector<vector<Edge>> &ming, ll start = 0) {
	ll n = g.size();
	ming.assign(n, vector<Edge>());
	ll mincost = 0;
	vector<bool> visited(n,false);
	priority_queue<Edge, vector<Edge>, function<bool(Edge,Edge)>> que(
		[](const Edge &x, const Edge &y){
			return x.cost != y.cost ? (x.cost > y.cost) : 
				(x.from != y.from ? x.from < y.from : x.to < y.to);
		}
	);
	
	que.push( Edge(-1, start, 0) );
	while (!que.empty()) {
		Edge e = que.top();
		que.pop();
		if (visited[e.to]) continue;
		visited[e.to] = true;
		if (e.from>=0) ming[e.from].push_back(e);
		mincost += e.cost;
		for(Edge f:g[e.to]) {
			if (!visited[f.to]) que.push(f);
		}
	}
	return mincost;
}



void dfs(vector<vector<Edge>> &g, ll v, ll p, vector<bool> &seen, map<pair<ll,ll>,ll> &m,vector<ll> &outdegree){
	seen[v]=true;
	for(Edge nextv : g[v]){
		if(seen[nextv.to])continue;
		dfs(g,nextv.to,v,seen,m,outdegree);
	}

	if(p==-1)return;

	if(outdegree[v]%2){//m[{v->p}]=1	
		if(p>v) m[{v,p}]=1;
		else m[{p,v}]=-1;
		outdegree[v]++;

	}else{//m[{v->p}]=-1	
		if(p>v) m[{v,p}]=-1;
		else m[{p,v}]=1;
		outdegree[p]++;
	}
	
}

signed main() {
	ll N,M;
	cin>>N>>M;
	if(M%2){
		p(-1);return 0;
	}

	vector<vector<Edge>> g(N);
	vector<ll> outdegree(N,0);
	map<pair<ll,ll>,ll> m;//0未決定、1そのまま、-1swap first->second
	rep(i,M){
		ll a,b;
		cin>>a>>b;
		a--;b--;
		Edge e(a,b,1);
		Edge f(b,a,1);
		g[a].push_back(e);
		g[b].push_back(f);

		if(a>b)swap(a,b);
		m[{a,b}]=1;
		outdegree[a]++;
	}
	
	vector<vector<Edge>> ming;
	ll mincost=prim(g, ming);
	debug(mincost);
	debug(ming);
	//出次数
	rep(i,ming.size()){
		for(Edge v:ming[i]){
			ll a=v.from,b=v.to;
			if(a>b)swap(a,b);
			m[{a,b}]=0;
			outdegree[a]--;
		}
	}
	//無向グラフ
	vector<vector<Edge>> treeg(N);
	rep(i,ming.size()){
		for(Edge v:ming[i]){
			ll a=v.from,b=v.to;
			treeg[a].push_back(Edge(a,b,1));
			treeg[b].push_back(Edge(b,a,1));
		}
	}	

	debug(m);
	vector<bool> seen(N,false);
	dfs(treeg,0,-1,seen,m,outdegree);

	debug(m);
	for(auto e:m){
		if(e.second==1){
			cout<<1+e.first.first<<' '<<1+e.first.second<<endl;
		}else{
			cout<<1+e.first.second<<' '<<1+e.first.first<<endl;
		}
	}

	return 0;
}



Measured memory_bytes: 45440