C++ for each, pulling from vector elements

c++, each, for-loop, vector

Solution

For next examples assumed that you use C++11. Example with ranged-based for loops:

for (auto &attack : m_attack) // access by reference to avoid copying
{  
    if (attack.m_num == input)
    {
        attack.makeDamage();
    }
}

You should use `const auto &attack` depending on the behavior of `makeDamage()`.

You can use `std::for_each` from standard library + lambdas:

std::for_each(m_attack.begin(), m_attack.end(),
        [](Attack * attack)
        {
            if (attack->m_num == input)
            {
                attack->makeDamage();
            }
        }
);

If you are uncomfortable using `std::for_each`, you can loop over `m_attack` using iterators:

for (auto attack = m_attack.begin(); attack != m_attack.end(); ++attack)
{  
    if (attack->m_num == input)
    {
        attack->makeDamage();
    }
}

Use `m_attack.cbegin()` and `m_attack.cend()` to get `const` iterators.

Problem

I am trying to do a foreach on a vector of attacks, each attack has a unique ID say, 1-3. The class method takes the keyboard input of 1-3. I am trying to use a foreach to run through my elements in m_attack to see if the number matches, if it does... do something. The problem I'm seeing is this: ``` a'for each' statement cannot operate on an expression of type "std::vector<Attack ``` Am I going about this totally wrong, I have C# experience and is kind of what I'm basing this on, any help would be appreciated. My code is as follows: In header ``` vector<Attack> m_attack; ``` In class ``` int Player::useAttack (int input) { for each (Attack* attack in m_attack) // Problem part { //Psuedo for following action if (attack->m_num == input) { //For the found attack, do it's damage attack->makeDamage(); } } } ```

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