#include "bits/stdc++.h"


using namespace std;

using i64 = long long;


template <typename T>
struct MemoryPool{
    int siz, idx;
    stack<int> st;
    vector<T*> pool;
    struct Index{
        int idx;
        friend bool operator==(const Index& a, const Index& b){return a.idx == b.idx;}
        friend bool operator!=(const Index& a, const Index& b){return a.idx != b.idx;}
    };
    MemoryPool() : siz(1), idx(0){}
    void resize(){
        pool.emplace_back(new T[siz]);
        siz <<= 1;
    }
    Index alloc(){
        if(!st.empty()){
            int res = st.top();
            st.pop();
            return {res};
        }
        if(++idx == siz)
            resize();
        return {idx};
    }
    void free(Index x){
        st.push(x.idx);
    }
    T& operator[](Index x){return pool[31 - __builtin_clz(x.idx)][x.idx & ~(1 << (31 - __builtin_clz(x.idx)))];}
};


template <typename T>
struct RedBlackTree{

    struct Node;
    using Index = typename MemoryPool<Node>::Index;

    struct Node{
        int siz, level;
        T key;
        bool red;
        typename MemoryPool<Node>::Index l, r;
        Node(){}
        Node(T val, bool red, bool leaf, int li = -1, int ri = -1) : key(val), siz(leaf), level(0), red(red){
            l = {li};
            r = {ri};
        }
    };

    MemoryPool<Node> pool;
    Index nil;
    RedBlackTree(){
        nil = pool.alloc();
        pool[nil] = Node(T(), false, false);
        pool[nil].l = pool[nil].r = nil;
    }

    Index build(vector<T>& a){
        nil = pool.alloc();
        pool[nil] = Node(T(), false, false);
        pool[nil].l = pool[nil].r = nil;
        int siz = a.size();
        vector<Index> v(siz);
        for(int i = 0; i < siz; ++i)
            v[i] = make(a[i]);
        while(siz != 1){
            int nex_siz = (siz + 1) >> 1;
            vector<Index> nex(nex_siz);
            for(int i = 0; i < (siz >> 1); ++i)
                nex[i] = merge(v[2 * i], v[2 * i + 1]);
            if(siz & 1)
                nex.back() = v.back();
            siz = nex_siz;
            v = move(nex);
        }
        return v[0];
    }

    void update(Index pi){
        if(pi == nil)
            return;
        auto& p = get(pi);
        auto& l = get(p.l);
        auto& r = get(p.r);
        p.siz = l.siz + r.siz;
        if(p.l != nil || p.r != nil)
            p.key = l.key;
        p.level = l.level + !l.red;
        assert(p.level == r.level + !r.red);
    }

    Index make(T val){
        Index idx = pool.alloc();
        pool[idx] = Node(val, false, true, nil.idx, nil.idx);
        pool[idx].level = 1;
        return idx;
    }

    Index mergeSub(Index ai, Index bi){
        auto& a = get(ai);
        auto& b = get(bi);
        assert(ai != nil && bi != nil);
        if(a.level < b.level){
            Index ci = mergeSub(ai, b.l);
            auto& c = get(ci);
            if(!b.red && c.red && get(c.l).red){
                if(!get(b.r).red){
                    b.l = c.l;
                    c.l = c.r;
                    c.r = b.r;
                    b.r = ci;
                    update(ci);
                    update(bi);
                    return bi;
                }
                else{
                    b.l = ci;
                    b.red ^= 1;
                    get(b.l).red ^= 1;
                    get(b.r).red ^= 1;
                    update(bi);
                    return bi;
                }
            }
            b.l = ci;
            update(bi);
            return bi;
        }
        else if(a.level > b.level){
            Index ci = mergeSub(a.r, bi);
            auto& c = get(ci);
            if(!a.red && c.red && get(c.r).red){
                if(!get(a.l).red){
                    a.r = c.r;
                    c.r = c.l;
                    c.l = a.l;
                    a.l = ci;
                    update(ci);
                    update(ai);
                    return ai;
                }
                else{
                    a.r = ci;
                    a.red ^= 1;
                    get(a.l).red ^= 1;
                    get(a.r).red ^= 1;
                    update(ai);
                    return ai;
                }
            }
            a.r = ci;
            update(ai);
            return ai;
        }
        else{
            a.red = false;
            b.red = false;
            Index d = pool.alloc();
            get(d) = Node(T(), true, false, ai.idx, bi.idx);
            update(d);
            return d;
        }
    }

    Index merge(Index ai, Index bi){
        if(ai == nil)
            return bi;
        if(bi == nil)
            return ai;
        Index ci = mergeSub(ai, bi);
        get(ci).red = false;
        return ci;
    }

    pair<Index, Index> split(Index ai, int k){
        auto& a = get(ai);
        if(k == 0)
            return make_pair(nil, ai);
        if(k == a.siz)
            return make_pair(ai, nil);
        Index li = a.l;
        Index ri = a.r;
        auto& l = get(li);
        pool.free(ai);
        if(k < l.siz){
            auto res = split(li, k);
            return make_pair(res.first, merge(res.second, ri));
        }
        else if(k > get(a.l).siz){
            auto res = split(ri, k - l.siz);
            return make_pair(merge(li, res.first), res.second);
        }
        else{
            return make_pair(li, ri);
        }
    }

    int lower_bound(Index pi, T x){
        if(pi == nil)
            return 0;
        int k = 0;
        while(get(pi).l != nil || get(pi).r != nil){
            auto& p = get(pi);
            assert(p.l != nil && p.r != nil);
            if(x < get(p.r).key){
                pi = p.l;
            }
            else{
                k += get(p.l).siz;
                pi = p.r;
            }
        }
        return k + (get(pi).key < x);
    }

    Index insert(Index pi, T val){
        int k = lower_bound(pi, val);
        auto res = split(pi, k);
        return merge(res.first, merge(make(val), res.second));
    }

    Index erase_index(Index pi, int k){
        auto res = split(pi, k + 1);
        auto res2 = split(res.first, k);
        pool.free(res2.second);
        return merge(res2.first, res.second);
    }

    Index erase_key(Index pi, T x){
        int k = lower_bound(pi, x);
        if(k == get(pi).siz || get(access(pi, k)).key != x)
            return pi;
        return erase_index(pi, k);
    }

    Index access(Index pi, int k){
        while(get(pi).l != nil || get(pi).r != nil){
            auto& p = get(pi);
            assert(p.l != nil && p.r != nil);
            if(get(p.l).siz <= k){
                k -= get(p.l).siz;
                pi = p.r;
            }
            else{
                pi = p.l;
            }
        }
        assert(k == 0);
        return pi;
    }

    Node& get(Index k){return pool[k];}
    Node& operator[](Index k){return pool[k];}
};



signed main(){
    int q;
    scanf("%d", &q);
    RedBlackTree<int> s;
    auto root = s.nil;
    for(int i = 0; i < q; ++i){
        int t, x;
        scanf("%d%d", &t, &x);
        if(t == 0){
            int idx = s.lower_bound(root, x);
            if(idx == s[root].siz || s[s.access(root, idx)].key != x)
                root = s.insert(root, x);
            printf("%d\n", s.get(root).siz);
        }
        else if(t == 2){
            root = s.erase_key(root, x);
        }
        else{
            int idx = s.lower_bound(root, x);
            printf("%d\n", idx != s[root].siz && s[s.access(root, idx)].key == x);
        }
    }
}



Measured memory_bytes: 12544