c++中stl 哈希函数_C ++ STL中的set :: size（）函数

末蓝、 2023-03-05 12:38 20阅读 0赞

c++中stl 哈希函数

## C ++ STL set :: size()函数 **(**C++ STL set::size() function**)** ##

**set::size() function** is a predefined function, it is used to get the size of a set, it returns the total number of elements of the set container.

**set :: size()函数**是预定义的函数，用于获取集合的大小，它返回集合容器中元素的总数。

**Prototype:**

**原型：**

set<T> st; //declaration
        set<T>::iterator it; //iterator declaration
        int sz=st.size();

**Parameter:** Nothing to pass

**参数：**无通过

**Return type:** Integer

**返回类型：**整数

**Usage:** The function returns size of the set

**用法：**该函数返回集合的大小

**Example:**

**例：**

For a set of integer,
        set<int> st;
        set<int>::iterator it;
        st.insert(4);
        st.insert(5);
        set content:
            4
            5
    
        int sz=st.size(); //sz=size of set that is 2
        Print sz; //prints 2

**Header file to be included:**

**包含的头文件：**

#include <iostream>
        #include <set>
        OR
        #include <bits/stdc++.h>

**C++ implementation:**

**C ++实现：**

#include <bits/stdc++.h>
    using namespace std;
    
    void printSet(set<int> st){
        
        set<int>:: iterator it;
        cout<<"Set contents are:\n";
        for(it=st.begin();it!=st.end();it++)
        cout<<*it<<" ";
        cout<<endl;
        
    }
    
    int main(){
        
        cout<<"Example of size function\n";
        set<int> st;
        set<int>:: iterator it;
        cout<<"inserting 4\n";
        st.insert(4);
        cout<<"inserting 6\n";
        st.insert(6);
        cout<<"inserting 10\n";
        st.insert(10);
        
        printSet(st); //printing current set
        
        //finding set sizeof
        
        cout<<"current set size is: "<<st.size();
        
        return 0;
    }

**Output**

**输出量**

Example of size function
    inserting 4      
    inserting 6      
    inserting 10     
    Set contents are:
    4 6 10  
    current set size is: 3

> 翻译自: [https://www.includehelp.com/stl/set-size-function-in-cpp-stl.aspx][https_www.includehelp.com_stl_set-size-function-in-cpp-stl.aspx]

c++中stl 哈希函数

[https_www.includehelp.com_stl_set-size-function-in-cpp-stl.aspx]: https://www.includehelp.com/stl/set-size-function-in-cpp-stl.aspx