Hello guys as i see this is a little error and i don't know how i can't fix it so the following are the main and the header file from the book i learn from:

main:

#include "../std_lib_facilities.h"

int main()
try
{
	vector<int>numbers;
	int number;

	cout << "Enter the numbers (\'|\' for terminating it) : ";
	while(cin >> number)
		numbers.push_back(number);

	int sum = 0;
	int num = 0;

	cout << "Enter the number of sums you want: ";
	cin >> num;

	for(int i = 0; i < numbers.size(); ++i)
		sum+=numbers[i];

	if(num >= numbers.size())
		error("Sorry the number of sums you want is out of range!!!\n");

	keep_window_open("exit");
	return 0;
}catch(exception& e){
	cerr << "Error: " << e.what() << endl;
	keep_window_open("exit");
	return 1;
}catch(...){
	cerr << "Error: Unknown exception"<< endl;
	keep_window_open("exit");
	return 1;
}

Header file:

/*
	simple "Programming: Principles and Practice using C++" course header to
	be used for the first few weeks.
	It provides the most common standard headers (in the global namespace)
	and minimal exception/error support.

	Students: please don't try to understand the details of headers just yet.
	All will be explained. This header is primarily used so that you don't have
	to understand every concept all at once.

	Revised April 25, 2010: simple_error() added
*/

#ifndef H112
#define H112 201004L

#include<iostream>
#include<fstream>
#include<sstream>
#include<cmath>
#include<cstdlib>
#include<string>
#include<list>
#include<vector>
#include<algorithm>
#include<stdexcept>

//------------------------------------------------------------------------------

#ifdef _MSC_VER
#include <hash_map>
using stdext::hash_map;
#else
#include <ext/hash_map>
using __gnu_cxx::hash_map;

namespace __gnu_cxx {

    template<> struct hash<std::string>
    {
        size_t operator()(const std::string& s) const
        {
            return hash<char*>()(s.c_str());
        }
    };

} // of namespace __gnu_cxx
#endif

//------------------------------------------------------------------------------

#define unordered_map hash_map

//------------------------------------------------------------------------------

typedef long Unicode;

//------------------------------------------------------------------------------

using namespace std;

template<class T> string to_string(const T& t)
{
	ostringstream os;
	os << t;
	return os.str();
}

struct Range_error : out_of_range {	// enhanced vector range error reporting
	int index;
	Range_error(int i) :out_of_range("Range error: "+to_string(i)), index(i) { }
};


// trivially range-checked vector (no iterator checking):
template< class T> struct Vector : public std::vector<T> {
	typedef typename std::vector<T>::size_type size_type;

	Vector() { }
	explicit Vector(size_type n) :std::vector<T>(n) {}
	Vector(size_type n, const T& v) :std::vector<T>(n,v) {}
	template <class I>
	Vector(I first, I last) :std::vector<T>(first,last) {}

	T& operator[](unsigned int i) // rather than return at(i);
	{
		if (i<0||this->size()<=i) throw Range_error(i);
		return std::vector<T>::operator[](i);
	}
	const T& operator[](unsigned int i) const
	{
		if (i<0||this->size()<=i) throw Range_error(i);
		return std::vector<T>::operator[](i);
	}
};

// disgusting macro hack to get a range checked vector:
#define vector Vector

// trivially range-checked string (no iterator checking):
struct String : std::string {
	
	String() { }
	String(const char* p) :std::string(p) {}
	String(const string& s) :std::string(s) {}
	template<class S> String(S s) :std::string(s) {}
	String(int sz, char val) :std::string(sz,val) {}
	template<class Iter> String(Iter p1, Iter p2) : std::string(p1,p2) { }

	char& operator[](unsigned int i) // rather than return at(i);
	{
		if (i<0||size()<=i) throw Range_error(i);
		return std::string::operator[](i);
	}

	const char& operator[](unsigned int i) const
	{
		if (i<0||size()<=i) throw Range_error(i);
		return std::string::operator[](i);
	}
};

#ifndef _MSC_VER
namespace __gnu_cxx {

    template<> struct hash<String>
    {
        size_t operator()(const String& s) const
        {
            return hash<std::string>()(s);
        }
    };

} // of namespace __gnu_cxx
#endif


struct Exit : runtime_error {
	Exit(): runtime_error("Exit") {}
};

// error() simply disguises throws:
inline void error(const string& s)
{
	throw runtime_error(s);
}

inline void error(const string& s, const string& s2)
{
	error(s+s2);
}

inline void error(const string& s, int i)
{
	ostringstream os;
	os << s <<": " << i;
	error(os.str());
}

#if _MSC_VER<1500
	// disgusting macro hack to get a range checked string:
	#define string String
	// MS C++ 9.0 have a built-in assert for string range check
	// and uses "std::string" in several places so that macro substitution fails
#endif

template<class T> char* as_bytes(T& i)	// needed for binary I/O
{
	void* addr = &i;	// get the address of the first byte
						// of memory used to store the object
	return static_cast<char*>(addr); // treat that memory as bytes
}


inline void keep_window_open()
{
	cin.clear();
	cout << "Please enter a character to exit\n";
	char ch;
	cin >> ch;
	return;
}

inline void keep_window_open(string s)
{
	if (s=="") return;
	cin.clear();
	cin.ignore(120,'\n');
	for (;;) {
		cout << "Please enter " << s << " to exit\n";
		string ss;
		while (cin >> ss && ss!=s)
			cout << "Please enter " << s << " to exit\n";
		return;
	}
}



// error function to be used (only) until error() is introduced in Chapter 5:
inline void simple_error(string s)	// write ``error: sā€™ā€™ and exit program
{
	cerr << "error: " << s << '\n';
	keep_window_open();		// for some Windows environments
	exit(1);
}

// make std::min() and std::max() accessible:
#undef min
#undef max

#include<iomanip>
inline ios_base& general(ios_base& b)	// to augment fixed and scientific
{
	b.setf(ios_base::fmtflags(0),ios_base::floatfield);
	return b;
}

// run-time checked narrowing cast (type conversion):
template<class R, class A> R narrow_cast(const A& a)
{
	R r = R(a);
	if (A(r)!=a) error(string("info loss"));
	return r;
}


inline int randint(int max) { return rand()%max; }

inline int randint(int min, int max) { return randint(max-min)+min; }

inline double sqrt(int x) { return sqrt(double(x)); }	// to match C++0x

#endif

compile the main file using this libraries(header file) and you'll see some thing strange really strange!!!

it's not an syntax error it's runtime one and a hard thing to understand : the following program has to do the following:

get some numbers into a vector by input
terminate the input
get the number of sums you want by input
check (the number of sums) if it's less than the vector size
printing the sum
or if the number of sums is equal or bigger than vector size it'll print error message

>>compile the main file using this libraries(header file) and you'll see some thing strange really strange!!!

Ok, I give up. What is so strange?? and please be specific.

ok so the program must do the following:

Enter the number ('|' for terminating it) : [U]15 16 17 |[/U]

and also after that it has to do the following

Enter the number of sums you want: [U]3[/U]

but indeed it does the following and that's the error

Enter the number of sums you want: Please enter exit to exit

and so i can't enter any input to get to the following statement.... that's seems to be very strange for me !!

any more specification you need?

Since | character is not a number you can not use cin>>num for data entry. Use sometime other than | for data termination, such as -1.

Second problem is that the Enter key '\n' is left in the keyboard buffer after numeric input. cin>>num does not remove it.

You need to do two things
1) clear the cin error
2) flush the input buffer of all remaining key values. See this link for the expanation

cin.clear();
    cin.ignore ( std::numeric_limits<std::streamsize>::max(), cin.widen ( '\n' ) );
Comments
954th thread about cin.ignore() on Daniweb!

Thank you ! you saved me a lot of more time!!! already have been in this for more than 7 hours trying and trying

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