获取string的尺寸和分配的空间大小

获取string的尺寸和已分配的内存空间大小

在C++中，获取字符串分配的内存大小，直接上代码…

#include<iostream>
using namespace std;


int main()
{
    //获取string的尺寸和已分配内存空间的尺寸
    string empty;
    sring small = "hello";
    string large = "获取string的尺寸和已分配内存空间的尺寸";

    cout << "empty size is "  << empty.size() << endl;
    cout << "small size is "  << small.size() << endl;
    cout << "large size is "  << large.size() << endl;

    cout << "empty capacity is" << empty.capacity() << endl; //在不同的编译器里，初始的空间不一定
    cout << "small capacity is" << small.capacity() << endl;
    cout << "large capacity is" << larege.capacity() << endl;

    //初始化分配内存时，按照n*16 - 1 的规则
    empty.resize(80); // 16*6 =96
    cout << "empty capacity is " << empty.capacity() << endl;
    for(int i = 1; i < 50; i++)
    {   
        empty += 'a';
    
    }   

    return 0;
}