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#include "ybwhead/ios.h"
int n, m;
const int maxn = 1e5 + 10;
int head[maxn], tot;
struct edge
{
    int v, nxt;
} e[maxn << 1];
void __ADD(int u, int v)
{
    e[++tot].v = v;
    e[tot].nxt = head[u];
    head[u] = tot;
}
void add(int u, int v)
{
    __ADD(u, v);
    __ADD(v, u);
}
int pos, tmp;
int w[maxn], v[maxn];
int dep[maxn], sz[maxn], c[maxn];
vector<pair<int, int>> q[maxn];
int ans[maxn];

int sum;
int siz[maxn];
int ms[maxn];
int rt;
int vis[maxn];
void gr(int u, int fa)
{
    // cout << u << endl;
    siz[u] = ms[u] = 1;
    for (int i = head[u]; i; i = e[i].nxt)
    {
        int v = e[i].v;
        if (v != fa && !vis[v])
        {
            gr(v, u);
            siz[u] += siz[v];
            if (siz[v] > ms[u])
                ms[u] = siz[v];
        }
    }
    ms[u] = max(ms[u], sum - siz[u]);
    if (ms[u] < ms[rt])
        rt = u;
}
int xp[maxn];
void getdep(int u, int fa)
{
    // cout << u << endl;
    ++xp[dep[u]];
    for (int i = head[u]; i; i = e[i].nxt)
    {
        int v = e[i].v;
        if (vis[v] || v == fa)
            continue;
        dep[v] = dep[u] + 1;
        getdep(v, u);
    }
}
void remove(int u, int fa, int d)
{
    xp[dep[u]] += d;
    for (int i = head[u]; i; i = e[i].nxt)
    {
        int v = e[i].v;
        if (v != fa && !vis[v])
        {
            remove(v, u, d);
        }
    }
}
void getans(int u, int fa)
{
    // cout << u << endl;
    for (int i = 0; i < q[u].size(); ++i)
    {
        int k = q[u][i].first - dep[u];
        if (k < 0)
            continue;
        ans[q[u][i].second] += xp[k];
    }
    for (int i = head[u]; i; i = e[i].nxt)
    {
        int v = e[i].v;
        if (v == fa || vis[v])
            continue;
        getans(v, u);
    }
}

void ga(int u)
{
    // cout << u << endl;
    int mxd = 0;
    dep[u] = 0;
    getdep(u, 0);
    for (int i = 0; i < q[u].size(); i++)
    {
        int k = q[u][i].first;
        ans[q[u][i].second] += xp[k];
    }
    for (int i = head[u]; i; i = e[i].nxt)
    {
        int v = e[i].v;
        if (!vis[v])
        {
            remove(v, u, -1);
            getans(v, u);
            remove(v, u, 1);
        }
    }
    remove(u, 0, -1);
}
void solve(int u)
{
    vis[u] = 1;
    ga(u);
    for (int i = head[u]; i; i = e[i].nxt)
    {
        int v = e[i].v;
        if (vis[v])
            continue;
        rt = 0;
        ms[0] = INT_MAX;
        sum = siz[v];
        gr(v, u);
        solve(rt);
    }
}
void clear()
{
    memset(head, 0, sizeof(head));
    tot = 0;
    memset(ans, 0, sizeof(ans));
    memset(vis, 0, sizeof(vis));
    for (int i = 1; i <= n; ++i)
    {
        q[i].clear();
    }
}
int main()
{
    int TTT;
    yin >> TTT;
    while (TTT--)
    {
        clear();
        yin >> n >> m;
        for (int i = 1; i < n; i++)
        {
            int a, b;
            yin >> a >> b;
            add(a, b);
        }
        for (int i = 1; i <= m; i++)
        {
            int x, y;
            yin >> x >> y;
            q[x].push_back(make_pair(y, i));
        }
        sum = n;
        ms[0] = INT_MAX;
        gr(1, 0);
        solve(rt);
        for (int i = 1; i <= m; i++)
        {
            yout << ans[i] << endl;
        }
    }
    return 0;
}