#include <stdio.h>
#include <string.h>

#define MAX_N 1000000
#define MOD 0xA299D
#define NIL -1

typedef struct {
  int v, next;
} hash;

hash l[MAX_N]; // liste simplu inlantuite alocate static
int lsize;
int h[MOD]; // inceputul listelor alocate static
int st[MAX_N], s; // stiva de pozitii refolosibile

inline bool hashFind(const int &x) {
  int i = h[x - (x / MOD) * MOD];

  while ((i != NIL) && (l[i].v != x)) {
    i = l[i].next;
  }
  return (i != NIL);
}
inline void hashInsert(const int &x) {
  int p = s ? st[--s] : lsize++;
  int hash = x - (x / MOD) * MOD;

  l[p].v = x;
  l[p].next = h[hash];
  h[hash] = p;
}
inline void hashExtract(const int &x) {
  int hash = x - (x / MOD) * MOD;
  int i = h[hash];

  if (l[i].v == x) {
    h[hash] = l[i].next;
  } else {
    while ((l[i].next != NIL) && (l[l[i].next].v != x)) {
      i = l[i].next;
    }
    if (l[i].next != NIL) {
      st[s++] = l[i].next;
      l[i].next = l[l[i].next].next;
    }
  }
}
int main(void) {
  FILE *f, *g;
  int testNum;
  int x;

  memset(h, NIL, MOD << 2);

  f = fopen("hashuri.in", "r");
  fscanf(f, "%d ", &testNum);
  g = fopen("hashuri.out", "w");
  for (; testNum; testNum--) {
    char c = fgetc(f);
    fscanf(f, "%d ", &x);
    if (c == '1') {
      hashInsert(x);
    } else if (c == '2') {
      hashExtract(x);
    } else {
      fputc(hashFind(x) + '0', g);
      fputc('\n', g);
    }
  }
  fclose(f);
  fclose(g);
  return 0;
}