/**************************************************************

     Problem: 3653

     User: idy002

     Language: C++

     Result: Accepted

     Time:9276 ms

     Memory:114596 kb

 ****************************************************************/

 #include <cstdio>

 #define min(a,b) ((a)<(b)?(a):(b))

 #define N 300010

 #define S 6000000

 typedef long long dnt;

 struct Node {

     dnt v;

     Node *ls, *rs;

 }pool[S], *tail=pool, *null=tail, *root[N];

 int n, m;

 int head[N], dest[N+N], next[N+N], etot;

 int fat[N], dep[N], siz[N], in[N], out[N], vin[N], idc, mdep;

 void adde( int u, int v ) {

     etot++;

     next[etot] = head[u];

     dest[etot] = v;

     head[u] = etot;

 }

 void dfs( int u ) {

     idc++;

     in[u] = idc;

     vin[idc] = u;

     siz[u] = ;

     for( int t=head[u]; t; t=next[t] ) {

         int v=dest[t];

         if( v==fat[u] ) continue;

         fat[v] = u;

         dep[v] = dep[u]+;

         dfs(v);

         siz[u] += siz[v];

     }

     out[u] = idc;

     if( dep[u]>mdep ) mdep=dep[u];

 }

 inline void update( Node *nd ) {

     nd->v = nd->ls->v + nd->rs->v;

 }

 Node *modify( Node *snd, int lf, int rg, int pos, int delta ) {

     Node *nnd = ++tail;

     if( lf==rg ) {

         nnd->v = snd->v + delta;

         return nnd;

     }

     int mid=(lf+rg)>>;

     if( pos<=mid ) {

         nnd->ls = modify( snd->ls, lf, mid, pos, delta );

         nnd->rs = snd->rs;

     } else {

         nnd->ls = snd->ls;

         nnd->rs = modify( snd->rs, mid+, rg, pos, delta );

     }

     update( nnd );

     return nnd;

 }

 dnt query( Node *nd, int lf, int rg, int L, int R ) {

     if( nd==null ) return 0LL;

     if( L<=lf && rg<=R )

         return nd->v;

     int mid=(lf+rg)>>;

     dnt rt = 0LL;

     if( L<=mid ) rt += query( nd->ls, lf, mid, L, R );

     if( R>mid ) rt += query( nd->rs, mid+, rg, L, R );

     return rt;

 }

 void build() {

     null->ls = null->rs = null;

     null->v = ;

     root[] = null;

     for( int i=; i<=idc; i++ ) {

         root[i] = modify( root[i-], , mdep, dep[vin[i]], siz[vin[i]]- );

     }

 }

 dnt query( int u, int k ) {

     dnt ans1 = (dnt) min(k,dep[u]-) * (siz[u]-);

     dnt ans2 = 0LL;

     if( siz[u]== ) return ans1;

     ans2 += query( root[out[u]], , mdep, dep[u]+, min( dep[u]+k, mdep ) );

     ans2 -= query( root[in[u]], , mdep, dep[u]+, min( dep[u]+k, mdep ) );

     return ans1 + ans2;

 }

 int main() {

     scanf( "%d%d", &n, &m );

     for( int i=,u,v; i<n; i++ ) {

         scanf( "%d%d", &u, &v );

         adde( u, v );

         adde( v, u );

     }

     fat[] = ;

     dep[] = ;

     dfs();

     build();

     for( int t=,u,k; t<=m; t++ ) {

         scanf( "%d%d", &u, &k );

         printf( "%lld\n", query(u,k) );

     }

 }