#include<cstdio>
#include<vector>
using namespace std;
FILE *f=fopen("hashuri.in","r");
FILE *g=fopen("hashuri.out","w");
vector<long> h[50000];
int n,nr,x,i,j,ok;
int main()
{
    fscanf(f,"%ld",&n);
    for(i=1;i<=n;i++)
    {
        fscanf(f,"%ld%ld",&x,&nr);
        if(x==1)
        {
            h[nr%50000].push_back(nr);
        }
        if(x==2)
        {
            for(j=0;j<h[nr%50000].size();j++)
            if(h[nr%50000][j]==nr) h[nr%5].erase(h[nr%50000].begin()+j,h[nr%50000].begin()+j+1);
        }
        if(x==3)
        {
            for(j=0;j<h[nr%50000].size();j++)
            if(h[nr%5][j]==nr) {ok=1;break;}
            if(ok==1) printf("1/n");
            else printf("0/n");
            ok=0;
        }
    }
}