#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define debug(x) cerr<<#x << " := " << x << endl;
#define bug cerr<<"-----------------------"<<endl;
#define FOR(a, b, c) for(int a = b; a <= c; ++ a)typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;template<class T> void _R(T &x) { cin >> x; }
void _R(int &x) { scanf("%d", &x); }
void _R(ll &x) { scanf("%lld", &x); }
void _R(double &x) { scanf("%lf", &x); }
void _R(char &x) { scanf(" %c", &x); }
void _R(char *x) { scanf("%s", x); }
void R() {}
template<class T, class... U> void R(T &head, U &... tail) { _R(head); R(tail...); }template<typename T>
inline T read(T&x){x=0;int f=0;char ch=getchar();while (ch<'0'||ch>'9') f|=(ch=='-'),ch=getchar();while (ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();return x=f?-x:x;
}const int inf = 0x3f3f3f3f;const int mod = 1e9+7;/**********showtime************/const int maxn = 1e5+9;vector<pii>mp[maxn];set   <pii>nmp[maxn];int dfn[maxn],low[maxn],belong[maxn],tim;int scc_cnt;int ans[maxn];int a[maxn], dp[maxn];stack<int>st;void dfs(int u, int fa) {dfn[u] = low[u] = ++tim;st.push(u);for(pii p : mp[u]){int v = p.fi;if(v == fa) continue;if(!dfn[v]) dfs(v, u);if(!belong[v]) low[u] = min(low[u], low[v]);}if(low[u] == dfn[u]) {scc_cnt++;nmp[scc_cnt].clear();int now;while(true){now = st.top(); st.pop();belong[now] = scc_cnt;a[scc_cnt] = max(a[scc_cnt], now);if(now == u) break;}}}void cal(int u, int fa) {dp[u] = a[u];for(pii p : nmp[u]) {int v = p.fi, id = p.se;if(v == fa) continue;cal(v, u);ans[id] = dp[v];dp[u] = max(dp[u], dp[v]);}}
int main(){int T;  scanf("%d", &T);while(T--) {int n,m;scanf("%d%d", &n, &m);for(int i=1; i<=n; i++) mp[i].clear(), dfn[i] = 0,dp[i] = 0, a[i] = 0,belong[i] = 0;for(int i=1; i<=m; i++) {int u,v;scanf("%d%d", &u, &v);mp[u].pb(pii(v, i));mp[v].pb(pii(u, i));ans[i] = 0;}tim = 0;scc_cnt = 0;for(int i=1; i<=n; i++) if(!dfn[i]) dfs(i, i);for(int u=1; u<=n; u++) {for(pii p : mp[u]) {int v = p.fi;if(belong[u] == belong[v]) continue;nmp[belong[u]].insert(pii(belong[v], p.se));}}cal(belong[n], belong[n]);for(int i=1; i<=m; i++) printf("%d %d\n", ans[i], ans[i] + (ans[i] != 0));}return 0;
}