C++ removing a element in string array which appears 5 times - c++

Question

Here is the code I have, I am having trouble finding a way to remove all Apple elem in the array. I am able to count the apples in the array. I hope someone can help...
string items[10] = { "Apple", "Oranges", "Pears", "Apple", "bananas", "Apple", "Cucumbers", "Apple", "Lemons", "Apple" };
//Counts the total amount of apples
int n = sizeof(items) / sizeof(items[0]);
cout << "Number of times Apple appears : "
<< count(items, items + n, "Apple");
//remove the element Apple from array
if (string items[].contains("Apple"))
{
items[].remove("Apple");
}

Answer 1

Some options you'd have would be:
Walk your array of items and substitute your "Apple" strings for empty strings.
Use a std::vector of strings and whether a) initialize it with the array of items and then call std::erase_if (C++20) to remove the "Apple" strings, or b) initialize it without elements and then call std::copy_if together with std::back_inserter to append the non-"Apple" strings.
[Demo]
#include <algorithm> // copy_if, transform
#include <iostream> // cout
#include <string>
#include <vector> // erase_if
int main()
{
{
std::string items[10] = { "Apple", "Oranges", "Pears", "Apple", "bananas", "Apple", "Cucumbers", "Apple", "Lemons", "Apple" };
std::transform(std::begin(items), std::end(items), std::begin(items), [](auto& s) {
return (s == "Apple" ? "" : s);
});
for (const auto& s : items) { std::cout << s << ", "; }
std::cout << "\n";
}
{
const std::string items[10] = { "Apple", "Oranges", "Pears", "Apple", "bananas", "Apple", "Cucumbers", "Apple", "Lemons", "Apple" };
std::vector<std::string> v{std::cbegin(items), std::cend(items)};
std::erase_if(v, [](auto& s) { return s == "Apple"; });
for (const auto& s : v) { std::cout << s << ", "; }
std::cout << "\n";
}
{
const std::string items[10] = { "Apple", "Oranges", "Pears", "Apple", "bananas", "Apple", "Cucumbers", "Apple", "Lemons", "Apple" };
std::vector<std::string> v{};
std::copy_if(std::cbegin(items), std::cend(items), std::back_inserter(v), [](auto& s) {
return s != "Apple";
});
for (const auto& s : v) { std::cout << s << ", "; }
}
}
// Outputs:
//
// , Oranges, Pears, , bananas, , Cucumbers, , Lemons, ,
// Oranges, Pears, bananas, Cucumbers, Lemons,
// Oranges, Pears, bananas, Cucumbers, Lemons,

Answer 2

The simplest and most efficient way to remove a number of elements in an array is to create a new array:
#include <iostream>
using namespace std;
int main()
{
string items[10] = { "Apple", "Oranges", "Pears", "Apple", "bananas", "Apple", "Cucumbers", "Apple", "Lemons", "Apple" };
string new_items[10];
int new_size = 0;
// construct new array
for (int i = 0; i < sizeof(items)/sizeof(string); i++) {
if ("Apple" != items[i]) {
new_items[new_size++] = items[i];
}
}
// print new array
for (int i = 0; i < new_size; i++) {
cout << new_items[i] << " ";
}
cout << endl;
return 0;
}