#include<stdio.h>
#include<stdlib.h>
#define MAX_ID 10000
int main(){
    int q;
    scanf("%d",&q);
    int subscriptions[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("Ivalid 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:
        subscriptions[id] = 1;
        break;
        case 2:
        subscriptions[id]  = 0;
        break;
        case 3:
        if(subscriptions[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");
    }
}
return 0;
}