#include <cstdio>
#include <cstring>

#define ALF 27

struct trie{
	int key,nrChild;
	trie* child[ALF];
	trie(){
		key=nrChild=0;
		memset(child,0,sizeof(child));
	}
};

FILE* fin=fopen("trie.in","r");
FILE* fout=fopen("trie.out","w");

trie root;
char buf[100];

void add(trie* ptr,char* c){
	while(*c!='\n'){
		if(ptr->child[*c-'a']==0){
			ptr->child[*c-'a']=new trie(),ptr->nrChild++;
		}
		ptr=ptr->child[*c-'a'],c++;
	}
	ptr->key++;
}
int del(trie* ptr,char* c){
	if(*c=='\n'){
		ptr->key--;
	}else if(del(ptr->child[*c-'a'],c+1)){
		ptr->child[*c-'a']=0;
		ptr->nrChild--;
	}
	if(ptr->key==0&&ptr->nrChild==0&&ptr!=&root){
		delete ptr;
		return 1;
	}
	return 0;
}
int num(trie* ptr,char* c){
	while(*c!='\n'){
		if(ptr->child[*c-'a']==0){
			return 0;
		}
		ptr=ptr->child[*c-'a'],c++;
	}
	return ptr->key;
}
int lcp(trie* ptr,char* c){
	int nr=0;
	while(*c!='\n'&&ptr->child[*c-'a']){
		ptr=ptr->child[*c-'a'],nr++,c++;
	}
	return nr;
}
int main(){
	int op,len;
	while(fgets(buf,sizeof(buf),fin)){
		switch(buf[0]){
			case '0':
				add(&root,buf+2);
				break;
			case '1':
				del(&root,buf+2);
				break;
			case '2':
				fprintf(fout,"%d\n",num(&root,buf+2));
				break;
			case '3':
				fprintf(fout,"%d\n",lcp(&root,buf+2));
				break;
		}
	}
	fclose(fin);
	fclose(fout);
	return 0;
}