字典树模版(指针) + (数组)

#include
using namespace std;
char ch[20];
struct node {
	int count;
	node *child[26];
};
node start;
node *temp = &start;
void insert(int p) {
	if(p == strlen(ch)){
		return ;
	}
	if(temp->child[ch[p] - 'a'] != NULL){
		temp = temp->child[ch[p] - 'a'];
	}else {
		temp->child[ch[p] - 'a'] = (struct node*)malloc(sizeof(struct node));
		temp = temp->child[ch[p] - 'a'];
		memset(temp, 0, sizeof(node));
	}
	temp->count++;
	insert(p+1);
}
int search(int p){
	if(p == strlen(ch)){
		return temp->count;
	}
	if(temp->child[ch[p] - 'a'] != NULL){
		temp = temp->child[ch[p] - 'a'];
	}else {
		return 0; 
	}
	return search(p + 1);
}
int main() {
	memset(temp, 0, sizeof(node));
	while(gets(ch)){
		temp = &start;
		if(strlen(ch) == 0){
			break;
		}
		insert(0);
	}
	while(gets(ch)){
		temp = &start;
		if(strlen(ch) == 0){
			break;
		}
		printf("%d\n",search(0));
	}
	return 0;
} 
#include
using namespace std;
int tree[1000010][26];
int num[1000010] = {0};
int pos = 1;
void build(char word[]) {
	int c = 0;
	for(int i = 0; word[i]; i++) {
		int n = word[i] - 'a';
		if(tree[c][n] == 0) {
			tree[c][n] = pos++;
		}
		c = tree[c][n];
		num[c]++;
	}
}
int find(char word[]) {
	int c = 0;
	for(int i = 0; word[i]; i++) {
		int n = word[i] - 'a';
		if(tree[c][n] == 0) {
			return 0;
		}
		c = tree[c][n];
	}
	return num[c];
}
int main() {
	char word[11];
	while(gets(word)) {
		if(word[0] == NULL) {
			break;
		}
		build(word);
	}
	while(gets(word)) {
		printf("%d\n",find(word));
	}
	return 0;
}

 

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