How can i remove the duplicate element in output / arrays?-CodePudding

#include <iostream>
using namespace std;

int main()
{
    const int ARRAY_SIZE = 10;
    int value[ARRAY_SIZE] = { 1, 2, 3, 4, 3, 4, 2, 3, 5, 6};
    int value2[100];
    for (int i = 0; i < ARRAY_SIZE; i  ) 
    {
        for (int j = i   1; j <= ARRAY_SIZE; j  )
        {
            if (value[i] == value[j]) 
            {
                cout << value[i] << " ";
            }
        }
    }
    return 0;
}

The output is

2 3 3 4 3

How can I make the output become 2 3 4 ?

Edit: I'm trying to print all numbers appearing more than once in the value array

I think I should create one more array to store value, but I stuck with it and don't know how to do it.

CodePudding user response：

It helps considerably to sort your array. Then you only need two indices:

a write index, starting at 0
a read index, starting at 1

Loop over your array using the read index. For every array[read] that has a duplicate value at array[read-1], IFF that value also does not exist at array[write], then copy it over and increment your write index.

Finally, the new length of your data is equal to your write index.

CodePudding user response：

You can use a std::map to count the number of times a value is in the array. If the number appears 2 or more times, then print it.

#include <iostream>
#include <map>

int main()
{
    const int ARRAY_SIZE = 10;
    int value[ARRAY_SIZE] = { 1, 2, 3, 4, 3, 4, 2, 3, 5, 6};
    std::map <int, int> mp;
    for(int i : value) 
          mp[i];
    for(const auto& p : mp) 
        if(p.second > 1)
            std::cout << p.first << ' ';
}

Link.