// editor4
#include<stdio.h>
#include<stdlib.h>
#define MAX_ID 10000
int main(){
    int q;
    scanf("%d",&q);
    int subscription[MAX_ID + 1] - {0};
    for(int i=0;i<q;i++){
        int query_type,id;
        scanf("%d",&query_type);
        if(query_type<1||query_type>4){
            printf("%Invalid input\n");
            continue;
        }
    }
    if(query_type==1||query_type==2||query_type==3){
        scanf("%d",&id);
        if(id<1||id>MAX_ID){
            printf("Invalid input\n");
            continue;
        }
    }
    switch(query_type){
        case 1:
        subscription[id]=1;
        break;
        case 2;
        subscription[id]=0;
        break;
        case 3:
        if(subscription[id]==1){
            printf("Subscribed\n");
        }else{
            printf("Not Subscribed\n");
        }
        break;
        case 4:{
            int count =0;
            for(int j=1;j<=MAX_ID;j++){
                if(subscription[j]==1){
                    count++;
                }
            }
            printf("%d\n",count);
            break;
        }
        default;
        printf("Invalid input\n");
    }
}