【C++语言实现通用插入排序算法】

插入排序算法的C++通用版本，支持任何以迭代器（或普通数组首、尾指针）传入的数组的就地排序。

myutil.h

 

代码:

#pragma once
#ifndef _MY_UTIL_H
#define _MY_UTIL_H

#include<iterator>  //iterator_traits

//template function to display arrays with new line printed when finish.
template<class Iterator>
void displayArr(const Iterator &beg, const Iterator &end){
  typedef typename std::iterator_traits<Iterator>::value_type Ty;
  std::copy(beg, end, std::ostream_iterator<Ty>(std::cout, " "));
  std::cout<<std::endl;
}

#endif

 

insertion_sort.h

 

代码:

#pragma once
#ifndef _INSERT_SORT_H
#define _INSERT_SORT_H

#include<iterator>  //iterator_traits

template<class Iterator, class cmp>
void insertSort(const Iterator &beg, const Iterator &end){
  typedef typename std::iterator_traits<Iterator>::value_type val_t;
  Iterator step = beg;
  Iterator insertPos;
  Iterator beforeInsertPos;
  for(++step; step != end; ++step){
    val_t key = *step;
    insertPos = step;
    beforeInsertPos = insertPos;
    for(--beforeInsertPos; cmp()(*beforeInsertPos, key); --beforeInsertPos){
      *insertPos-- = *beforeInsertPos;
      if(beforeInsertPos == beg)
        break;
    }//end of for
    *insertPos = key;
  }// end of for
}// end of insertion sort

#endif

main.cpp

 

代码:

#include<iostream>
#include<string>
#include<vector>
#include<list>

#include"myutil.h"  //displayArr
#include"insertion_sort.h"  //insertSort

using std::cout;
using std::endl;
using std::vector;
using std::string;
using std::list;

int main(int argc, char **argv)
{
  int intArr[ ] = { 231, -547, -54, 54, 0, -1, 45, -54, 123, 9, -54 };
  int *intArrEnd = intArr + sizeof(intArr) / sizeof(*intArr);

  double doubleArr[ ] = { 0.0, -28.7, 465.2 };
  double *doubleArrEnd = doubleArr + sizeof(doubleArr) / sizeof(*doubleArr);

  string strArr[] = {"月夜幻影", "bill", "billhoo", "Alex", "alex", "Petter"};
  string *strArrEnd = strArr + sizeof(strArr) / sizeof(*strArr);

  vector<string> strVec(strArr, strArrEnd);
  list<string> strList(strArr, strArrEnd);

  cout<<"before insertion sort..."<<endl;
  displayArr<int*>(intArr, intArrEnd);
  displayArr<double*>(doubleArr, doubleArrEnd);
  displayArr<string*>(strArr, strArrEnd);
  displayArr(strVec.begin(), strVec.end());
  displayArr(strList.begin(), strList.end());

  //do insertion sort in ascending order
  insertSort<int*, std::greater<int>>(intArr, intArrEnd);
  insertSort<double*, std::greater<double>>(doubleArr, doubleArrEnd);
  insertSort<string*, std::greater<string>>(strArr, strArrEnd);
  insertSort<vector<string>::iterator, std::greater<string>>(strVec.begin(), strVec.end());
  insertSort<list<string>::iterator, std::greater<string>>(strList.begin(), strList.end());

  cout<<"\nascending order:"<<endl;
  displayArr<int*>(intArr, intArrEnd);
  displayArr<double*>(doubleArr, doubleArrEnd);
  displayArr<string*>(strArr, strArrEnd);
  displayArr(strVec.begin(), strVec.end());
  displayArr(strList.begin(), strList.end());

  //do insertion sort in descending order
  insertSort<int*, std::less<int>>(intArr, intArrEnd);
  insertSort<double*, std::less<double>>(doubleArr, doubleArrEnd);
  insertSort<string*, std::less<string>>(strArr, strArrEnd);
  insertSort<vector<string>::iterator, std::less<string>>(strVec.begin(), strVec.end());
  insertSort<list<string>::iterator, std::less<string>>(strList.begin(), strList.end());

  cout<<"\ndescending order:"<<endl;
  displayArr<int*>(intArr, intArrEnd);
  displayArr<double*>(doubleArr, doubleArrEnd);
  displayArr<string*>(strArr, strArrEnd);
  displayArr(strVec.begin(), strVec.end());
  displayArr(strList.begin(), strList.end());

  return EXIT_SUCCESS;
}