#include <bits/stdc++.h>
using namespace std;
const int MAXN = 300;
struct EDGE {
  int u, v;
  int type;
};
int n, m, deg[MAXN];
vector<EDGE> edges;
vector<int> G[MAXN];
bool vis[MAXN * MAXN];
bool alive[MAXN][MAXN];
bool visN[MAXN];
vector<int> ans;
void add_edge(int u, int v, int type = 0) {
  edges.push_back(EDGE{u, v, type});
  edges.push_back(EDGE{v, u, type});
  G[u].push_back(edges.size() - 2);
  G[v].push_back(edges.size() - 1);
  deg[u]++, deg[v]++;
  alive[u][v] = alive[v][u] |= type ^ 1;
}
void input() {
  memset(visN, 0, sizeof(visN));
  memset(vis, 0, sizeof(vis));
  memset(alive, 0, sizeof(alive));
  memset(deg, 0, sizeof(deg));
  edges.clear();
  ans.clear();
  for (int i = 0; i < MAXN; i++) G[i].clear();
  scanf("%d%d", &n, &m);
  for (int i = 0, u, v; i < m; i++) {
    scanf("%d%d", &u, &v);
    add_edge(u, v);
  }
}
void add_Graph() {
  vector<int> tmp;
  for (int i = 1; i <= n; i++)
    if (deg[i] % 2 == 1) {
      tmp.push_back(i);
    }
  printf("%d\n", n - tmp.size());
  for (int i = 0; i < tmp.size(); i += 2) {
    add_edge(tmp[i], tmp[i + 1], 1);
  }
}
void dfs(int u) {
  visN[u] = 1;
  for (int i = 0; i < G[u].size(); i++)
    if (!vis[G[u][i] >> 1]) {
      EDGE &e = edges[G[u][i]];
      int v = e.v;
      vis[G[u][i] >> 1] = 1;
      dfs(v);
    }
  ans.push_back(u);
}
int main() {
  int T;
  scanf("%d", &T);
  while (T--) {
    input();
    add_Graph();
    for (int i = 1; i <= n; i++)
      if (!visN[i]) {
        dfs(i);
        for (int j = 0; j < ans.size() - 1; j++) {
          int u = ans[j], v = ans[j + 1];
          if (alive[u][v]) {
            alive[u][v] = alive[v][u] = 0;
            printf("%d %d\n", u, v);
          }
        }
        ans.clear();
      }
  }
}
