学步园

/*2014. 01 .11  by Arby*/
/*c++ primer 7.12 编程练习*/
#include <iostream>
using namespace std;

void give_value(int arr[], int size, int value);
void show_array(int arr[], int size);

int main()
{
	/*初始化*/
	const int arr_size = 5;
	int array_give[arr_size];
	int value;

	/*操作*/
	cout <<"give the value of you want:";
	cin >> value;
	give_value(array_give, arr_size, value);
	show_array(array_give, arr_size);

	cin.get();
	cin.get();
	return 0;
}

/*因为数组传递的是原数组，因此返回类型不用管*/
void give_value(int arr[], int size, int value)
{
	for(int i = 0; i < size; i++)
	{
		arr[i] = value;
	}
}

void show_array(int arr[], int size)
{
	for(int i = 0; i < size; i++)
	{
		cout << arr[i] << " ";
	}
}

4.

/*2014. 01 .11  by Arby*/
/*c++ primer 7.12 编程练习*/
#include <iostream>
using namespace std;

void give_value(int *begin, int *end, int value);
void show_array(int arr[], int size);

int main()
{
	/*初始化*/
	const int arr_size = 5;
	int array_give[arr_size];
	int value;

	/*操作*/
	cout <<"give the value of you want:";
	cin >> value;
	give_value(array_give, array_give+arr_size, value);
	show_array(array_give, arr_size);

	cin.get();
	cin.get();
	return 0;
}

/*因为数组传递的是原数组，因此返回类型不用管, 因为这里要进行赋值，因此不能设置为const*/
void give_value(int *begin,  int *end, int value)
{
	int *ps;
	for(ps = begin; ps != end; ps++)
	{
		*ps = value;
	}
}

void show_array(int arr[], int size)
{
	for(int i = 0; i < size; i++)
	{
		cout << arr[i] << " ";
	}
}

5.

/*2014. 01 .11  by Arby*/
/*c++ primer 7.12 编程练习*/
#include <iostream>
using namespace std;
double give_max(double arr_size[], int size);

int main()
{
	/*初始化*/
	const int arr_size = 4;
	double arr[arr_size] = {54, 23, 34, 59};
	double max_value;
	/*操作*/
	max_value = give_max(arr, arr_size);
	cout << "the max value is: " << max_value << endl;

	cin.get();
	cin.get();
	return 0;
}

double give_max(double arr_size[], int size)
{
	if(size < 0)
		cout << "the size is wrong";
	double max = arr_size[0];
	for(int i = 0; i < size; i++)
	{
		if(arr_size[i] > max)
		{
			max = arr_size[i];
		}
	}

	return max;
}

8.

/*2014. 01 .11  by Arby*/
/*c++ primer 7.12 编程练习*/
/*字符串中字符的替换*/
#include <iostream>
using namespace std;
int replace(char *str, char c1, char c2);

int main()
{
	/*初始化*/
	const int char_size = 20;
	char str[20] = "asfllksddsdhg";
	char c1 = 'd';
	char c2 = 'z';
	int number = 0;
	/*操作*/
	number = replace(str, c1, c2);
	cout << str << endl;
	cout << "the number is: " << number << endl;

	cin.get();
	cin.get();
	return 0;
}

int replace(char *str, char c1, char c2)
{  
	int count = 0;
	int i = 0;
	while(*(str+i) != '\0')
	{
		if(*(str+i) == c1)
		{
			*(str+i) = c2;
			count++;
		}
		i++;
	}
	return count;
}

1

/*2014. 01 .11  by Arby*/
/*c++ primer 7.12 编程练习*/
/*条件检测*/
#include <iostream>
using namespace std;
double soft_average(double x, double y);

int main()
{
	/*初始化*/
	double x, y;
	double result;
	/*操作*/
	cout << "please enter two number of you want to accumulate: ";
	cin >> x >> y;
	while(x != 0 && y != 0)
	{
		result = soft_average(x, y);
		cout << "the result is: " << result << endl;
		cin>>x >> y;
	}
	cout << "enter find 0 causing quit." << endl;

	cin.get();
	cin.get();
	return 0;
}

double soft_average(double x, double y)
{
	double result = 2.0 * x * y / (x + y);
	return result;
}