思路
题意:题目为中文题,这里不再过多阐述。
思路1:可以在读入单词表的过程中将单词分解,用map将它一 一记录
思路2:利用字典树,这个方法较快些,下面代码中会分别给出数组和结构体指针两种形式的字典树,指针形式的有时可能会因题目内存限制而导致Memory Limit Exceeded,这时就可选择数组形式的。不过对于本题来说不用担心。
AC代码
代码1:map打表
#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
map<string, int> table;
int main()
{
std::ios::sync_with_stdio(false);
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
table.clear();
string s;
while(getline(cin, s))
{
if(s[0] == '\0')
break;
string ss = "";
for(int i = 0; i < s.size(); i++)
{
ss += s[i];
table[ss]++;
}
}
while(cin >> s)
{
cout << table[s] << endl;
}
}
代码2:数组形式的字典树
#include<bits/stdc++.h>
using namespace std;
const int maxnode = 400001;
const int maxs = 27;
char s[10 + 10];
int trie[maxnode][maxs] ;
int sum[maxnode] ;
int node = 0;
void inserts(char *t)
{
int len = strlen(t);
int cur = 0;
for(int i = 0; i < len; i++)
{
int p = t[i] - 'a';
if(!trie[cur][p])
trie[cur][p] = ++node;
sum[trie[cur][p]]++;
cur = trie[cur][p];
}
}
int searchs(char *t)
{
int len = strlen(t);
int cur = 0;
for(int i = 0; i < len; i++)
{
int p = t[i] - 'a';
if(!trie[cur][p])
return 0;
cur = trie[cur][p];
}
return sum[cur];
}
int main()
{
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
memset(trie, 0, sizeof(trie));
memset(sum, 0, sizeof(sum));
while(gets(s) != NULL)
{
if(s[0] == '\0')
break;
inserts(s);
}
while(scanf("%s", s) != EOF)
{
cout << searchs(s) << endl;
}
}
代码3:结构体指针形式的字典树
//#include<bits/stdc++.h>
#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
char s[10+10];
struct Trie
{
Trie* next[26];
int sum;
Trie()
{
for(int i = 0; i < 26; i++)
next[i] = NULL;
sum = 0;
}
}root;
void inserts(char *s)
{
Trie* p = &root;
int len = strlen(s);
for(int i = 0; i < len; i++)
{
int cur = s[i] - 'a';
if(p->next[cur] == NULL)
{
p->next[cur] = new Trie;
}
p = p->next[cur];
p->sum++;
}
}
int finds(char *s)
{
Trie* p = &root;
int len = strlen(s);
for(int i = 0; i < len; i++)
{
int cur = s[i] - 'a';
if(p->next[cur] == NULL)
return 0;
else
p = p->next[cur];
}
return p->sum;
}
int main()
{
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
while(gets(s) != NULL)
{
if(s[0] == '\0')
break;
inserts(s);
}
while(scanf("%s", s) != EOF)
{
cout << finds(s) << endl;
}
}
原文地址:https://www.cnblogs.com/KeepZ/p/11370931.html
时间: 2024-10-13 15:24:18