[C++知识库]数据结构、算法与应用 C++语言描述（第二版）第一章1-9

1.

//原因：
//x和y是值传递，只需将x和y改为引用传递
#include <iostream>
using namespace std;

void swap(int& x, int& y)
{
	int temp = x;
	x = y;
	y = temp;
}
int main()
{
	int x1 = 25;
	int y1 = 35;
	cout << "x1 = " << x1 << " y1 = " << y1 << endl;
	swap(x1, y1);
	cout << "x1 = " << x1 << " y1 = " << y1 << endl;
	return 0;
}

2.

//模板函数count
#include <iostream>
using namespace std;

template <class T>
int count(T *array, const int size, const T &value)
{
	int num = 0;
	for (int i = 0; i < size; ++i)
	{
		if (array[i] == value)
		{
			++num;
		}
	}
	return num;
}

int main()
{
	int array[10] = { 12,17,54,32,66,89,17,49,17,65 };
	const int size = sizeof(array) / sizeof(array[0]);
	const int value = 17;
	cout << count(array, size, value) << endl;
	return 0;
}

3.

//模板函数fill
#include <iostream>
using namespace std;

template <class T>
void fill(T* array, const int size)
{
	for (int i = 0; i < size; ++i)
	{
		cin >> array[i];
	}
}

int main()
{
	const int size = 5;
	int array[size];
	fill(array, size);
	return 0;
}

4.

//模板函数inner_product
#include <iostream>
using namespace std;

template <class T>
T inner_product(T* array1, T* array2, const int size)
{
	T result = 0;
	for (int i = 0; i < size; ++i)
	{
		result += array1[i] * array2[i];
	}
	return result;
}

int main()
{
	const int size = 10;
	int array1[size] = { 1,2,3,4,5,6,7,8,9,10 };
	int array2[size] = { 10,9,8,7,6,5,4,3,2,1 };
	cout << "The result is:" << inner_product(array1, array2, size) << endl;
	return 0;
}

5.

//模板函数iota
#include <iostream>
using namespace std;

template <class T>
void iota(T* array, const int size, const int value)
{
	for (int i = 0; i < size; ++i)
	{
		array[i] = value + i;
	}
}

int main()
{
	const int size = 10;
	const int value = 1;
	int array[size] = { 0 };
	iota(array, size, value);
	for (int i = 0; i < size; ++i)
	{
		cout << array[i] << " ";
	}
	return 0;
}

6.

//模板函数is_sorted
#include <iostream>
using namespace std;

template <class T>
bool is_sorted(T* array, const int size)
{
	bool result = true;
	if (size == 1)
	{
		return true;
	}
	for (int i = 1; i < size; ++i)
	{
		if (array[i] < array[i - 1])
		{
			result = false;
			break;
		}
	}
	return result;
}

int main()
{
    const int size = 10;
	int array[size] = { 0,1,2,3,4,5,6,7,8,9 };
	if (is_sorted(array, size))
	{
		cout << "The array id ordered!";
	}
	else
	{
		cout << "The array id unordered!";
	}
	return 0;
}

7.

//模板函数is_sorted
#include <iostream>
using namespace std;

template <class T>
int mismatch(T* array1, T* array2, const int size)
{
	for (int i = 0; i < size; ++i)
	{
		if (array1[i] != array2[i])
		{
			return i;
		}
	}
	return size;
}

int main()
{
    const int size = 10;
	int array1[size] = { 0,1,2,3,4,5,6,7,8,9 };
	int array2[size] = { 0,1,2,3,4,5,6,7,8,10 };
	if (mismatch(array1, array2, size) == size)
	{
		cout << "The two arrays are the same!";
	}
	else
	{
		cout << "Minimum index:" << mismatch(array1, array2, size) << endl;
	}
	return 0;
}

8.

#include <iostream>
using namespace std;

int abc(int a, int b, int c) {}
float abc(int a, int b, int c) {}  //abc重定义,无法重载仅按返回类型区分的函数

int main()
{
	return 0;
}

9.

#include <iostream>
using namespace std;

int abc(int a, int b, int c)
{
	return a + b * c;
}

float abc(float a, float b, float c)
{
	return a + b * c;
}

int main()
{
	cout << abc(1, 2, 3) << endl;
	cout << abc(1.0F, 2.0F, 3.0F) << endl;
	cout << abc(1, 2, 3.0F) << endl;     //错误,参数类型(int,int,float)  
	cout << abc(1.0, 2.0, 3.0) << endl;  //错误,参数类型(double,double,doule)
	return 0;
}