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How to use std::sort to sort an array in C++

Tags:

c++

sorting

People also ask

How do you sort an array by sorting in C++?

first – is the index (pointer) of the first element in the range to be sorted. last – is the index (pointer) of the last element in the range to be sorted. For example, we want to sort elements of an array 'arr' from 1 to 10 position, we will use sort(arr, arr+10) and it will sort 10 elements in Ascending order.

Which function is used to sort arrays C++?

std::sort() in C++ STL. It generally takes two parameters, the first one being the point of the array/vector from where the sorting needs to begin and the second parameter being the length up to which we want the array/vector to get sorted.

How do you sort an array sort?

Using the sort() Method In Java, Arrays is the class defined in the java. util package that provides sort() method to sort an array in ascending order. It uses Dual-Pivot Quicksort algorithm for sorting. Its complexity is O(n log(n)).


In C++0x/11 we get std::begin and std::end which are overloaded for arrays:

#include <algorithm>

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

If you don't have access to C++0x, it isn't hard to write them yourself:

// 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;
}

#include <algorithm>
static const size_t v_size = 2000;
int v[v_size];
// Fill the array by values
std::sort(v,v+v_size); 

In C++11:

#include <algorithm>
#include <array>
std::array<int, 2000> v;
// Fill the array by values
std::sort(v.begin(),v.end()); 

If you don't know the size, you can use:

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

Even if you do know the size, it's a good idea to code it this way as it will reduce the possibility of a bug if the array size is changed later.


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


//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;
    }


}