C++排序字符串数组

Question

我正在尝试排序一个字符串数组,但它没有排序任何东西....我做错了什么？

string namesS[MAX_NAMES];

int compare (const void * a, const void * b){
    return ( *(char*)a - *(char*)b );
}


void sortNames(){

    qsort(namesS, MAX_NAMES, sizeof(string), compare);
}

Answer 1

这是C++,而不是C.对字符串数组进行排序很容易.

#include <string>
#include <vector>
#include <algorithm>

std::vector<std::string> stringarray;
std::sort(stringarray.begin(), stringarray.end());

Answer 2

std::qsort继承自标准C库.不起作用.

您需要std::sort用于排序字符串.

具体来说,转换std::string为void*然后char*是未定义的,将无法工作.

Answer 3

CPP中的算法排序与qsort具有相同的复杂度:

#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
using namespace std;

bool compare(string a, string b){
    cout << "compare(" << a << "," << b << ")" << endl;
    return (a.compare(b) < 0);
}

int main () {

    string mystrs[] = {"www","ggg","bbb","ssss","aaa"};
    vector<string> myvector (mystrs, mystrs + 5);               
    vector<string>::iterator it;

  sort (myvector.begin(), myvector.end(), compare);

  cout << "vector contains:";
  for (it=myvector.begin(); it!=myvector.end(); ++it)
    cout << " " << *it;

  cout << endl;

  return 0;
}