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#include <cstdio>
#include <cstring>
#include <cctype>
using namespace std;
struct node{
int occurences;
struct node *edge[26];
node(){
occurences = 0;
for(int i = 0; i < 26; i++){
edge[i] = NULL;
}
}
};
node *head = NULL;
void Initialize(){
head = new node;
}
void Insert(char word[]){
node *current = head;
int len = strlen(word), index;
for(int i = 0; i < len; i++, current = current -> edge[index]){
index = tolower(word[i]) - 'a';
if(current -> edge[index] == NULL){
current -> edge[index] = new node;
}
}current -> occurences++;
}
int Search(char word[]){
node *current = head;
int len = strlen(word), index;
for(int i = 0; i < len; i++, current = current -> edge[index]){
index = tolower(word[i]) - 'a';
if(current -> edge[index] == NULL) return 0;
}
return current -> occurences;
}
int LongestPrefix(char word[]){
node *ptr = head;
int i, j, index, prefix = 0, len = strlen(word);
for(i=0; i<len; i++, ptr = ptr -> edge[index]){
index = tolower(word[i] - 'a');
if(ptr -> edge[index] == NULL) return prefix;
int verges = 0;
for(j=0; j<26; j++){
verges += !!((ptr -> edge[index]) -> edge[j]);
}
if((ptr -> edge[index]) -> occurences || verges >= 1){
prefix = i+1;
}
}
return prefix;
}
void Delete(char word[]){
node *ptr = head, *depth = NULL;
int i, j=-1, k, index, len = strlen(word), verges = 0;
for(i=0; i<len; i++, ptr = ptr -> edge[index]){
index = tolower(word[i] - 'a');
if(ptr -> edge[index] == NULL) return;
if(i != len-1 && ptr -> occurences){
depth = ptr;
j = i;
}
verges = 0;
for(k = 0; i && k < 26; k++){
verges += !!(ptr -> edge[k]);
}if(verges > 1 && i > j){
j = i;
depth = ptr;
}
}if(ptr -> occurences == 0) return;
verges = 0;
for(i=0; i<26; i++){
verges += !!(ptr -> edge[i]);
}
if(ptr -> occurences > 1 || ((ptr -> occurences == 1) && verges)){
ptr -> occurences--;
return;
}
if(depth == NULL){
index = tolower(word[0] - 'a');
ptr = head -> edge[index];
head -> edge[index] = NULL;
for(i=1; i<len; i++){
index = tolower(word[i] - 'a');
node *temp = ptr;
ptr = ptr -> edge[index];
delete temp;
}delete ptr;
}else{
k = len - j;
index = tolower(word[j] - 'a');
node *temp = depth;
depth = depth -> edge[index];
temp -> edge[index] = NULL;
for(i=1; i<k; i++){
index = tolower(word[j+i] - 'a');
temp = depth;
depth = depth -> edge[index];
delete temp;
}delete depth;
}
}
int main(){
Initialize();
freopen("trie.in", "r", stdin);
freopen("trie.out", "w", stdout);
int task;
char word[21], ch=0;
while(1){
if(isdigit(ch)){
task = ch - 48;
}else{
scanf("%d", &task);
}
scanf("%s", word);
switch(task){
case 0:{
Insert(word);
break;
}
case 1:{
Delete(word);
break;
}
case 2:{
printf("%d\n", Search(word));
break;
}
case 3:{
printf("%d\n", LongestPrefix(word));
break;
}
}
while(1){
ch = getchar();
if(isdigit(ch) || ch == EOF){
break;
}
}
if(ch == EOF) break;
}
return 0;
}