Jak używać STD:: sort do sortowania tablicy w C++

Jak używać standardowej biblioteki szablonów std::sort() do sortowania tablicy zadeklarowanej jako int v[2000];

Czy C++ dostarcza jakąś funkcję, która może uzyskać indeks początku i końca tablicy?

 91
Author: Varaquilex, 2011-05-05

13 answers

W C++0x / 11 otrzymujemy std::begin oraz std::end które są przeciążone dla tablic:

#include <algorithm>

int main(){
  int v[2000];
  std::sort(std::begin(v), std::end(v));
}

Jeśli nie masz dostępu do C++0x, nie jest trudno napisać je samemu:

// for container with nested typedefs, non-const version
template<class Cont>
typename Cont::iterator begin(Cont& c){
  return c.begin();
}

template<class Cont>
typename Cont::iterator end(Cont& c){
  return c.end();
}

// const version
template<class Cont>
typename Cont::const_iterator begin(Cont const& c){
  return c.begin();
}

template<class Cont>
typename Cont::const_iterator end(Cont const& c){
  return c.end();
}

// overloads for C style arrays
template<class T, std::size_t N>
T* begin(T (&arr)[N]){
  return &arr[0];
}

template<class T, std::size_t N>
T* end(T (&arr)[N]){
  return arr + N;
}
 111
Author: Xeo,
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2013-08-28 19:04:41
#include <algorithm>
static const size_t v_size = 2000;
int v[v_size];
// Fill the array by values
std::sort(v,v+v_size); 

W C++11:

#include <algorithm>
#include <array>
std::array<int, 2000> v;
// Fill the array by values
std::sort(v.begin(),v.end()); 
 70
Author: Naszta,
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2013-09-19 20:16:45

Jeśli nie znasz rozmiaru, możesz użyć:

std::sort(v, v + sizeof v / sizeof v[0]);

Nawet jeśli znasz rozmiar, dobrym pomysłem jest zakodowanie go w ten sposób, ponieważ zmniejszy to możliwość wystąpienia błędu, jeśli rozmiar tablicy zostanie zmieniony później.

 31
Author: j_random_hacker,
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2011-05-05 12:04:18

You can sort it std::sort(v, v + 2000)

 18
Author: Mayank,
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2015-01-23 16:22:38
//It is working
#include<iostream>
using namespace std;
void main()
{
    int a[5];
    int temp=0;
    cout<<"Enter Values"<<endl;
    for(int i=0;i<5;i++)
    {
        cin>>a[i];
    }
    for(int i=0;i<5;i++)
    {
        for(int j=0;j<5;j++)
        {
            if(a[i]>a[j])
            {
                temp=a[i];
                a[i]=a[j];
                a[j]=temp;
            }
        }
    }
    cout<<"Asending Series"<<endl;
    for(int i=0;i<5;i++)
    {
        cout<<endl;
        cout<<a[i]<<endl;
    }


    for(int i=0;i<5;i++)
    {
        for(int j=0;j<5;j++)
        {
            if(a[i]<a[j])
            {
                temp=a[i];
                a[i]=a[j];
                a[j]=temp;
            }
        }
    }
    cout<<"Desnding Series"<<endl;
    for(int i=0;i<5;i++)
    {
        cout<<endl;
        cout<<a[i]<<endl;
    }


}
 3
Author: wahid Butt,
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2015-08-10 05:39:48

Możesz użyć sort () W C++ STL. składnia funkcji sort ():

 sort(array_name, array_name+size)      

 So you use  sort(v, v+2000);
 2
Author: rashedcs,
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2017-03-12 01:34:51

To takie proste ... C++ udostępnia funkcję w STL (Standard Template Library) o nazwie sort, która działa od 20% do 50% szybciej niż ręcznie kodowany quick-sort.

Oto przykładowy kod użycia:

std::sort(arr, arr + size);
 2
Author: risheek reddy,
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2019-07-14 04:15:32

Sortowanie C++ za pomocą funkcji sort

#include <bits/stdc++.h>
 using namespace std;

vector <int> v[100];

int main()
{
  sort(v.begin(), v.end());
}
 1
Author: Mahedi Hasan Durjoy,
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2017-03-22 05:59:48

Użyj C++ std::sort Funkcja:

#include <algorithm>
using namespace std;

int main()
{
  vector<int> v(2000);
  sort(v.begin(), v.end());
}
 1
Author: Toby Speight,
Warning: date(): Invalid date.timezone value 'Europe/Kyiv', we selected the timezone 'UTC' for now. in /var/www/agent_stack/data/www/doraprojects.net/template/agent.layouts/content.php on line 54
2017-03-22 16:26:47
//sort by number
bool sortByStartNumber(Player &p1, Player &p2) {
    return p1.getStartNumber() < p2.getStartNumber();
}
//sort by string
bool sortByName(Player &p1, Player &p2) {
    string s1 = p1.getFullName();
    string s2 = p2.getFullName();
    return s1.compare(s2) == -1;
}
 1
Author: user5465465465,
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2019-01-16 22:28:32

Z biblioteką Ranges, która pojawi się w C++20, możesz użyć

ranges::sort(arr);

Bezpośrednio, gdzie arr jest wbudowaną tablicą.

 1
Author: L. F.,
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2019-07-14 04:17:20

Metoda sortowania Bez std::sort:

// sorting myArray ascending
int iTemp = 0;
for (int i = 0; i < ARRAYSIZE; i++)
{
    for (int j = i + 1; j <= ARRAYSIZE; j++)
    {
        // for descending sort change '<' with '>'
        if (myArray[j] < myArray[i])
        {
            iTemp = myArray[i];
            myArray[i] = myArray[j];
            myArray[j] = iTemp;
        }
    }
}

Uruchom kompletny przykład:

#include <iostream> // std::cout, std::endl /* http://en.cppreference.com/w/cpp/header/iostream */
#include <cstdlib>  // srand(), rand()      /* http://en.cppreference.com/w/cpp/header/cstdlib */
#include <ctime>    // time()               /* http://en.cppreference.com/w/cpp/header/ctime */


int main()
{
    const int ARRAYSIZE = 10;
    int myArray[ARRAYSIZE];

    // populate myArray with random numbers from 1 to 1000
    srand(time(0));
    for (int i = 0; i < ARRAYSIZE; i++)
    {
        myArray[i] = rand()% 1000 + 1;
    }

    // print unsorted myArray
    std::cout << "unsorted myArray: " << std::endl;
    for (int i = 0; i < ARRAYSIZE; i++)
    {
        std::cout << "[" << i << "] -> " << myArray[i] << std::endl;
    }
    std::cout << std::endl;

    // sorting myArray ascending
    int iTemp = 0;
    for (int i = 0; i < ARRAYSIZE; i++)
    {
        for (int j = i + 1; j <= ARRAYSIZE; j++)
        {
            // for descending sort change '<' with '>'
            if (myArray[j] < myArray[i])
            {
                iTemp = myArray[i];
                myArray[i] = myArray[j];
                myArray[j] = iTemp;
            }
        }
    }

    // print sorted myArray
    std::cout << "sorted myArray: " << std::endl;
    for (int i = 0; i < ARRAYSIZE; i++)
    {
        std::cout << "[" << i << "] -> " << myArray[i] << std::endl;
    }
    std::cout << std::endl;

    return 0;
}
 0
Author: user6021501,
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2016-03-05 08:47:44

Możesz użyć,

 std::sort(v.begin(),v.end());
 -1
Author: Rohit Hajare,
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2016-02-02 05:55:12