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This is the first Big-small algorithm of contact.
Give you a tree. Everyone's red or white at first.
At first, the root is red dot. Two operations change a dot to a red dot and ask how far a white dot is from the nearest red dot.
Coincidentally, when we save sqrt(m) inquiries and look up each white dot, I just compare the distance between dis and sqrt(m) red dots and then run dijstra once every sqrt(m).

/*
    if you can't see the repay
    Why not just work step by step
    rubbish is relaxed
    to ljq
*/
#include <cstdio>
#include <cstring>
#include <iostream>
#include <queue>
#include <cmath>
#include <map>
#include <stack>
#include <set>
#include <sstream>
#include <vector>
#include <stdlib.h>
#include <algorithm>
//#pragma comment(linker, "/STACK:10240000,10240000")
using namespace std;
 
#define dbg(x) cout<<#x<<" = "<< (x)<< endl
#define dbg2(x1,x2) cout<<#x1<<" = "<<x1<<" "<<#x2<<" = "<<x2<<endl
#define dbg3(x1,x2,x3) cout<<#x1<<" = "<<x1<<" "<<#x2<<" = "<<x2<<" "<<#x3<<" = "<<x3<<endl
#define max3(a,b,c) max(a,max(b,c))
#define min3(a,b,c) min(a,min(b,c))
 
typedef pair<int,int> pll;
typedef long long ll;
typedef unsigned long long ull;
const ull hash1 = 201326611;
const int inf = 0x3f3f3f3f;
const int _inf = 0xc0c0c0c0;
const ll INF = 0x3f3f3f3f3f3f3f3f;
const ll _INF = 0xc0c0c0c0c0c0c0c0;
const ll mod =  (int)1e9+7;
 
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
ll ksm(ll a,ll b,ll mod){int ans=1;while(b){if(b&1) ans=(ans*a)%mod;a=(a*a)%mod;b>>=1;}return ans;}
ll inv2(ll a,ll mod){return ksm(a,mod-2,mod);}
void exgcd(ll a,ll b,ll &x,ll &y,ll &d){if(!b) {d = a;x = 1;y=0;}else{exgcd(b,a%b,y,x,d);y-=x*(a/b);}}//printf("%lld*a + %lld*b = %lld\n", x, y, d);
//ull ha[MAX_N],pp[MAX_N];
 
inline int read()
{
    int date = 0,m = 1; char ch = 0;
    while(ch!='-'&&(ch<'0'|ch>'9'))ch = getchar();
    if(ch=='-'){m = -1; ch = getchar();}
    while(ch>='0' && ch<='9')
    {
        date = date*10+ch-'0';
        ch = getchar();
    }return date*m;
}
 
/*namespace sgt
{
    #define mid ((l+r)>>1)
 
    #undef mid
}*/
 
/*int root[MAX_N],cnt,sz;
namespace hjt
{
    #define mid ((l+r)>>1)
    struct node{int l,r,maxx;}T[MAX_N*40];
 
    #undef mid
}*/
const int MAX_N = 100025;
int depth[MAX_N],fa[MAX_N][21],lg[MAX_N],d[MAX_N];
vector<int> vt[MAX_N],tmp;
void dfs(int x,int fath)
{
    depth[x] = depth[fath]+1;
    fa[x][0] = fath;
    for(int i = 1;(1<<i)<=depth[x];++i)
        fa[x][i] = fa[fa[x][i-1]][i-1];
    for(int i = 0;i<vt[x].size();i++)
    {
        int v = vt[x][i];
        if(v==fath) continue;
        dfs(v,x);
    }
}
int lca(int x,int y)
{
    if(depth[x]<depth[y])
        swap(x,y);
    while(depth[x]>depth[y])
        x = fa[x][lg[depth[x]-depth[y]]-1];
    if(x==y)
        return x;
    for(int k = lg[depth[x]]-1;k>=0;--k)
        if(fa[x][k]!=fa[y][k])
            x = fa[x][k], y = fa[y][k];
    return fa[x][0];
}
void dij()
{
    priority_queue<pair<int ,int > > q;
    for(int i = 0;i<tmp.size();++i) q.push(make_pair(0,tmp[i]));
    while(!q.empty())
    {
        pair<int,int > top = q.top();q.pop();
        int v = top.second;
        if(d[v]<-(top.first)) continue;
        for(int i = 0;i<vt[v].size();++i)
        {
            int e = vt[v][i];
            if(d[e]>d[v]+1)
            {
                d[e] = d[v]+1;
                q.push(make_pair(-d[e],e));
            }
        }
    }
}
int main()
{
    //ios::sync_with_stdio(false);
    //freopen("a.txt","r",stdin);
    //freopen("b.txt","w",stdout);
    int opt,a,b,n,m,block,x;
    scanf("%d%d",&n,&m);
    for(int i = 1;i<=n;++i)
    lg[i] = lg[i-1] + (1<<lg[i-1]==i);
    memset(d,0x3f,sizeof(d));
    for(int i = 1;i<n;++i)
    {
        scanf("%d%d",&a,&b);
        vt[a].push_back(b);
        vt[b].push_back(a);
    }
    dfs(1,0);//depth[-1] illegal
    d[1] = 0;
    tmp.push_back(1);
    block = sqrt(m);
    while(m--)
    {
        scanf("%d%d",&opt,&x);
        if(opt==1)
        {
            d[x] = 0;
            tmp.push_back(x);
            if(tmp.size()==block)
            {
                dij();
                vector<int > now;
                swap(tmp,now);
            }
        }
        else
        {
            int ans = d[x];
            for(int i = 0;i<tmp.size();++i)
            {
                ans = min(ans,depth[tmp[i]] + depth[x]-2*depth[lca(x,tmp[i])]);
            }
            printf("%d\n",ans);
        }
    }
    //fclose(stdin);
    //fclose(stdout);
    //cout << "time: " << (long long)clock() * 1000 / CLOCKS_PER_SEC << " ms" << endl;
    return 0;
}