Frequency Word

/***
17.9 Design a method to find the frequency of occurrences of any given word in a book.
IDEA: map a book in a hash table or a map. key is word and value is the frequency
***/

#include<iostream>
#include<fstream>
#include<map>
#include<string>

using namespace std;

map<string, int> mapbook(char *book) {
       ifstream mybook(book);
       string str;
       map<string, int> dic;
       map<string, int> :: iterator it;

       while(mybook.good()) {
              mybook>>str;
              it = dic.find(str);
              if(it != dic.end()) {
                     it->second += 1;
              } else {
                     dic.insert(pair<string, int>(str, 1));
              }
       }
       return dic;
}

int lookup(string word, char *book) {
       map<string, int> dic;
       dic = mapbook(book);

       if(dic.count(word)) return dic[word];
       else return 0;

}

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