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

#define maxL 30

FILE*f=fopen("trie.in","r");
FILE*g=fopen("trie.out","w");

int s,l,app,L,ch;
char sir[maxL];

struct Trie{
	
	int nr,nrfii; Trie *son[27];
	
	Trie(){
		
		nr = nrfii = 0;
		
		memset(son,0,sizeof(son));
	}
	
	
};

Trie *r = new Trie;

void insert( Trie *nod ){
	
	if ( s == l ){
		++(nod->nr);
		return ;
	}
	
	ch = sir[s] - 'a' + 1;
	
	if ( nod->son[ ch ] == 0 ){
		
		nod->son[ ch ] = new Trie; 
		(nod->nrfii)++;
		
	}
	
	++s;
	
	insert( nod->son[ ch ] ); 
	
}

bool erase ( Trie *nod , int s ){
	
	if ( s == l ){
		--(nod -> nr);
	}
	else{
		ch = sir[s] - 'a' + 1;
		if ( erase( nod -> son[ ch ] , s + 1 ) ){
			nod -> son[ ch ] = NULL;
			--nod -> nrfii;
		}
	}
	
	if ( (!(nod -> nrfii) && !(nod -> nr) && nod != r) || s == l  ){
		delete nod;
		return 1;
	}
	
	return 0;
	
}

void appear ( Trie *nod ){
	
	if ( s == l ){
		app = nod -> nr;
		return ;
	}
	
	ch = sir[s] - 'a' + 1;
	
	if ( nod -> son[ ch ]  && s < l ){
		++s;
		appear ( nod -> son[ ch ] );
	}
	
}

void sc ( Trie *nod ){
	
	++L;
	
	ch = sir[s] - 'a' + 1;
	
	if ( nod -> son[ ch ] && s < l ){
		++s;
		sc( nod -> son[ ch ] );
	}
	
}

int main () {
	
	
	
	while ( fgets(sir+1,maxL-2,f) ){
		
		switch (sir[1]){
			
			case '0' :{
				
				s = 3; l = strlen(sir+1); insert(r);
				
				break;
			}
			case '1' :{
				
				l = strlen(sir+1); erase(r,3);
				
				break;
			}
			case '2' :{
				
				s = 3; app = 0; l = strlen(sir+1); appear(r);
				
				fprintf(g,"%d\n",app );
				
				break;
			}
			case '3' :{
				
				s = 3; L = -1; l = strlen(sir+1); sc(r); 
				
				fprintf(g,"%d\n",L);
				
				break;
			}
			
		}
		
	}
	
	
	fclose(f);
	fclose(g);
	
	return 0;
}