/* Problem URL: https://codeforces.com/contest/2204/problem/D */

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template <class T, class comp = less<>>
using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;

#define V vector

#define rmin(a, b) a = min(a, b)
#define rmax(a, b) a = max(a, b)

#define rep(i, lim) for (int i = 0; i < (lim); i++)
#define nrep(i, s, lim) for (int i = s; i < (lim); i++)

#define repv(i, v) for (auto &i : (v))
#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
#define sortv(v) sort(v.begin(), v.end())
#define all(v) (v).begin(), (v).end()

using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vvvvi = vector<vvvi>;

using ll = long long;

using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vvvvl = vector<vvvl>;

template<class v>
auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
    os << vec[0];
    for (size_t i = 1; i < vec.size(); i++) {
        os << ' ' << vec[i];
    }
    os << '\n';
    return os;
}

template<class v>
auto operator>>(istream &is, vector<v> &vec)->istream& {
    for (auto &i : vec) {
        is >> i;
    }
    return is;
}

template<class v>
auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
    for (auto &i : vec) {
        os << i[0];
        for (size_t j = 1; j < i.size(); j++) {
            os << ' ' << i[j];
        }
        os << '\n';
    }
    return os;
}

template<class v>
auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
    for (auto &i : vec) {
        for (auto &j : i) {
            is >> j;
        }
    }
    return is;
}

const int oo = INT32_MAX >> 1;
const ll OO = INT64_MAX >> 1;


void pre()
{

}

#define TEST 1

void solve()
{
    int n, m;
    cin >> n >> m;

    vvi graph(n);
    while (m--) {
        int a, b;
        cin >> a >> b;
        a--, b--;
        graph[a].push_back(b);
        graph[b].push_back(a);
    }

    vi dis(n, oo);
    function<pair<int, bool>(int)> bfs = [&](int i) -> pair<int, bool> {
        dis[i] = 0;
        queue<int> q;
        q.push(i);
        bool pos = true;
        int sz = 1;

        while (!q.empty()) {
            auto i = q.front();
            q.pop();

            repv(j, graph[i]) {
                if (dis[j] > dis[i] + 1) {
                    dis[j] = dis[i] + 1;
                    q.push(j);
                    sz++;
                    continue;
                }

                if ((dis[j] & 1) == (dis[i] & 1)) {
                    pos = false;
                }
            }
        }

        return {sz, pos};
    };

    V<bool> vis(n);

    int ans = 0;
    rep(i, n) {
        if (dis[i] != oo) {
            continue;
        }

        auto [c, p] = bfs(i);

        if (!p) {
            continue;
        }

        array<int, 2> co = {0, 0};
        function<void(int, int)> dfs = [&](int i, int g) {
            co[g]++;
            vis[i] = true;

            repv(j, graph[i]) {
                if (vis[j]) {
                    continue;
                }

                dfs(j, g^1);
            }
        };

        dfs(i, 0);
        ans += max(co[0], co[1]);
    }

    cout << ans << '\n';
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    pre();

    int t;
    (TEST && cin >> t) || (t = 1);
    while (t--) {
        solve();
    }
}