AcWing 835. Trie字符串统计

Trie 字符串统计

#include <iostream>

using namespace std;

const int N = 1e6 + 10;

int son[N][26], cnt[N], idx;
char str[N];

void insert(char str[]){
	int p = 0;
	for(int i = 0; str[i]; i++){
		int u = str[i] - 'a';
		if(!son[p][u]) son[p][u] = ++idx;
		p = son[p][u];
	}
	cnt[p]++;
}
int query(char str[]){
	int p = 0;
	for(int i = 0; str[i]; i++){
		int u = str[i] - 'a';
		if(!son[p][u]) return 0;
		p = son[p][u];
	}
	return cnt[p];
}
int main(){
	int n;
	scanf("%d", &n);
	while(n--){
		char op[2];
		scanf("%s%s", op, str);
		if(op[0] == 'I') insert(str);
		else printf("%d\n", query(str));
	}
	return 0;
}

#include <iostream>

using namespace std;

const int N = 1e6 + 10;

int son[N][26], cnt[N], idx;// 下标是 0 的点，既是根节点，又是空节点
char str[N];
void insert(char str[]){
    int p = 0;
    for(int i = 0; str[i]; i++){
        int u = str[i] - 'a';
        if(!son[p][u]) son[p][u] = ++idx;
        p = son[p][u];
    }
    
    cnt[p]++;
}

int query(char str[]){
    int p = 0;
    for(int i = 0; str[i]; i++){
        int u = str[i] - 'a';
        if(!son[p][u]) return 0;
        p = son[p][u];
    }
    
    return cnt[p];
}

int main(){
    int n;
    scanf("%d", &n);
    while(n--){
        char op[2];
        scanf("%s%s", op, str);
        if(op[0] == 'I') insert(str);
        else printf("%d\n", query(str));
    }
    
    return 0;
}