I'm working on an assignment for school where my teacher wants me to convert each member of an array of a class if it's int member is greater than 300. I can make it work for the first value of 300, since that's what find_if returns. But how do I make it work for all members? Here's some code:

#include "Test.h"
#include "Drawer.h"
#include <iostream>
using namespace std;
#include <Algorithm>

CDrawer gCanvas(RGB(0,0,0));
void Draw(CTest [], int);
bool myCountIf(CTest const &);
bool myCountIf2(CTest const &);
// ICA  19 ** Fill in the required blocks, labels and pauses are supplied
int main( void )
{
  CTest a[150];
  CTest b[150];
  CTest c[150];

  for (int i(0); i < 150; ++i)
  {
	  a[i] = CTest(300);
	  b[i]= CTest((i + 1) * 4);
	  c[i] =CTest(rand() % 600);
  }

  cout << "a - Fixed 300\n";
  Draw( a, 150 );
  cin.get();
  cout << "b - Increment\n";
  Draw( b, 150 );
  cin.get();
  cout << "c - Random\n";
  Draw( c, 150 );
  cin.get();

// Min and Max of c here
  cout << "Min of c : " << min_element(c, c + 150)->GetY() << endl;
  cout << "Max of c : " << max_element(c, c + 150)->GetY() << endl;
  cin.get();

// Count of 200, Count > 300 here
  cout << "Count of b == 200 : " << count_if(b, b + 150, myCountIf) << endl;
  cout << "Count of b > 300 : " << count_if(b, b + 150, myCountIf2) << endl;
  cin.get();

// Find and Set() 200 in b
  cout << "Found 200 in b, setting to RED\n";
  find_if(b, b + 150, myCountIf)->Set();
  Draw( b, 150 );
  cin.get();

// Find and Set() all > 300 in c here ***************************
//for_each doesnt seem to work here
  cout << "Found > 300 in c, setting to RED\n";
  for_each(c, b + 150, find_if(b, b + 150, myCountIf)->Set());
  Draw( c, 150 );
  cin.get();
	return 0;
}

void Draw(CTest Array[], int iCount)
{
	gCanvas.Clear();
	for (int i(0); i < iCount; ++i)
		gCanvas.AddLine(i * 5, 600, i * 5, 600 - Array[i].GetY(),5, Array[i].GetColor());
	gCanvas.Render();
}

bool myCountIf(CTest const & iVal)
{
	return iVal == CTest(200);
}
bool myCountIf2(CTest const & iVal)
{
	return !(iVal < CTest(300));
}

//class CTest - 
#pragma once
#include "Drawer.h"


class CTest
{
	int _iHeight;
	COLORREF _Color;
public:
	CTest(int iH = 0, COLORREF Col = RGB(rand() % 255, rand() % 255, rand() % 255)):_iHeight(iH), _Color(Col) {}
	//accessors
	int GetY()const {return _iHeight;}
	COLORREF GetColor()const {return _Color;}
	//mutators
	void Set()
	{
		_Color = RGB(255, 0, 0);
	}
                //operators
	bool operator<(CTest const & RHS) const
	{
		return _iHeight < RHS._iHeight;
	}
	bool operator==(CTest const & RHS)const
	{
		return _iHeight == RHS._iHeight;
	}

	~CTest(void);
};

The problem is in the part with all the *'s.
I'm pretty new to the STL (other than basic sorting and vectors), so any help would be appreciated.

find_if returns an iterator to the matched item, and for_each is retarded. ;)

CTest *it = b;
CTest *end = b + 150;

while ( ( it = find_if ( it, end, myCountIf ) ) != end ) {
  it->Set();
  ++it;
}
commented: Excellent! =) +5

find_if returns an iterator to the matched item, and for_each is retarded. ;)

CTest *it = b;
CTest *end = b + 150;

while ( ( it = find_if ( it, end, myCountIf ) ) != end ) {
  it->Set();
  ++it;
}

Lol. Thanks, I already solved it with a similar loop. I was thinking that there was a single function to do the whole loop for me :P .

Here's what i did:

CTest * lp = c - 1; //last found pointer (start at 1 before c)
  //this loop is a bit confusing...
  while (lp < c + 150)
	  (lp = find_if(++lp, c + 150, myCountIf2))->Set();
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