c++資料結構 --unorder_map

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#include <iostream>#include <unordered_map>using namespace std;class Book{private:    string num;    string name;public:    Book() {};    Book(string num,string name) { this ->name = name;this ->num = num;};    string getNum() { return num;};    string getName() { return name;};};int main(){    unordered_map<string,Book>lib;    Book b("001","進階語言程式設計") ;    lib[b.getNum()] = b;    unordered_map<string,Book>::iterator it;    it  = lib.find( *(new string("001")) );    if ( it != lib.end() )        cout << (it ->second).getName();    else        cout << "沒有給元素!";    return 0;}

unsigned int JSHash(const char *str){    unsigned int hash = 1315423911;    while (*str){        hash ^= ((hash << 5) + (*str++) + (hash >> 2));    }    return (hash & 0x7FFFFFFF);}class StrHash{public:    size_t operator()(const string& s) const {        return JSHash(s.c_str());    }};class StrCompare{public:    bool operator()(const string& a,const string& b) const {        return (a==b);    }};

字元雜湊及字串比較函數

note:

1.內部實現為: hasht_table

2.樣本中,已string為key,unorder_map已經為string建立了hash值計算函數,所以無需重寫(貌似是這樣的)

3.(Todo)詳解具體使用方法

c++資料結構 --unorder_map