报错代码

#include<iostream>
#include<list>
#include<random>
#include<algorithm>
using namespace std;
int main(){
    list<int> a;
    for (int i=0;i<10;++i) a.push_back(rand());
    for (auto num: a) cout << num << ' ';

    sort(a.begin(),a.end());
    cout << endl;
    for (auto num: a) cout << num << ' ';
    system("pause");
    return 0;
}

报错

报错信息很长，这里截取一些部分，以便搜索：
In instantiation of ‘void std::__sort(_RandomAccessIterator, _RandomAccessIterator, _Compare) [with _RandomAccessIterator = std::_List_iterator; _Compare = __gnu_cxx::__ops::_Iter_less_iter]’


stl_algo.h:4828:18: required from 'void std::sort(_RAIter, _RAIter) [with _RAIter = std::_List_iterator]


stl_algo.h:1968:22: error: no match for ‘operator-’ (operand types are ‘std::_List_iterator’ and ‘std::_List_iterator’)
1968 | std::__lg(__last - __first) * 2,


stl_bvector.h:214:39: note: no known conversion for argument 1 from ‘std::_List_iterator’ to ‘const std::_Bit_iterator_base&’
214 | operator-(const _Bit_iterator_base& __x, const _Bit_iterator_base& __y)

原因

list容器不支持随机访问，不能直接使用algorithm的sort

解决方案

使用list专用的sort，即写成 a.sort()（类似python），具体如下，成功运行

#include<iostream>
#include<list>
#include<random>
#include<algorithm>
using namespace std;
int main(){
    list<int> a;
    for (int i=0;i<10;++i) a.push_back(rand());
    for (auto num: a) cout << num << ' ';

    // `list` type container should use its specialized sort function
    a.sort(); 
    cout << endl;
    for (auto num: a) cout << num << ' ';
    system("pause");
    return 0;
}