c++上机（第一次）

1. Read the codes carefully on page 230 and page 248 of the book, or on page 247 and page 266 of the e-book, then answer the questions as below:
  1.1 Describe the main data structure of Stack；
  1.2 Describe the differences in the data storage of Stash and Stack.

  Notice: The answer can be written in English or Chinese.

1.1
Stack只能在表尾进行操作。
Stack满足后进先出的储存原则，通过栈顶指针Top进行控制。如果栈空，则Top指向栈底，否则Top指向当前栈顶元素的下一位。
Stack的元素是以结点的形式储存的，其中Date保存的是数据的地址而不是数据的实体。
Stack元素的内存空间并不一定连续，Stack是一种链栈。
Stack的基本操作：
1.插入。Stack只能在栈顶位置插入，即表尾，将元素存入当前Top指针指向的位置，然后Top++；
2.删除。Stack的删除只能弹出栈顶的元素。
3.判断是否为空。当Top==Low(栈底)时，Stack为空。
等等

1.2
①.Stash有inflate方法用作膨胀空间，Stack中没有相关操作
②.Stack保存元素是是产生结点的模式，Stack的Date并不储存数据实体，而是储存数据的地址
③.Stack的元素储存位置并不一定连续，是一种链栈

2. Create a program that opens a text file in English and counts 
   the words number in that file.
   NOTE: I)  Words are seperated by spaces(one or more spaces).

         II) A number or continuous numbers are not WORD.

#include<cstdio>
#include<cstring>
#include<iostream>
#include<fstream>
#include<vector>
using namespace std;
const int MAX = 50;

int Count() {
	int cou = 0, flag = 0;
	char ch;
	ifstream text;
	text.open("Question 2.txt", ios::in);//打开.txt文件
	while (!text.eof()) {//逐字符读取
		ch = text.get();
		if ((ch >= 'A'&&ch <= 'Z') || (ch >= 'a'&&ch <= 'z')) {//如果是字母则flag置1
			flag = 1;
		}
		else
		{
			if (flag) {//如果遇到非字母则表示已经读取了一个单词，则cou++，同时flag置0
				cou++;
				flag = 0;
			}
		}
	}
	if (flag)cou++;//最后一个单词可能没有停止记录的机会
	return cou;
}
int main()
{
	int res;
	res = Count();
	cout << "该文本共有" << res << "个单词" << endl;
	return 0;
}

3. Create a class Point, and finish the following functions as below:
  3.1 Define two member variables, X and Y, as coordinate, and the other member variable R is radius;
  3.2 Define a member function, Distace, to calculate the distance between two points.
 3.3 Define a member function, Relationship, to judge the relationship such as seperation, intersection, tangent(intenally or externally tangent) between two circles. 

  Note: You can define appropriate parameters according to your member functions.

#include<cstdio>
#include<cstring>
#include<iostream>
#include<math.h>
using namespace std;

class Circle {
public:
	void setCircle(int x, int y, int r) {//设置
		X = x;
		Y = y;
		R = r;
	}

	int Distance(Circle b) {//4.2 计算两个圆的距离
		int dis, disx, disy;
		disx = X - b.X;//x方向上的距离
		disy = Y - b.Y;//y方向上的距离
		dis = sqrt(pow(disx, 2) + pow(disy, 2));
		return dis;
	}

	void Relationship(Circle b) {//4.3 判断两个圆的关系
		if (this->Distance(b) < (R + b.R))cout << "圆a与圆b相交" << endl;
		else {
			if (this->Distance(b) == (R + b.R))cout << "圆a与圆b外切" << endl;
			else
			{
				if (this->Distance(b) == abs(R - b.R))cout << "圆a与圆b内切" << endl;
				else
				{
					if(this->Distance(b) > (R + b.R))cout << "圆a与圆b外离" << endl;
					else
					{
						cout << "圆a与圆b内离" << endl;
					}
				}
			}
		}
	}

private:
	int X;
	int Y;
	int R;

};

int main()
{
	Circle a, b;
	int ax, ay, ar;
	int bx, by, br;
	cout << "请输入圆a的x坐标"; cin >> ax;
	cout << "请输入圆a的y坐标"; cin >> ay;
	cout << "请输入圆a的半径"; cin >> ar;
	cout << "请输入圆b的x坐标"; cin >> bx;
	cout << "请输入圆b的y坐标"; cin >> by;
	cout << "请输入圆b的半径"; cin >> br;
	a.setCircle(ax, ay, ar);
	b.setCircle(bx, by, br);

	cout << "两个圆心的距离是" << a.Distance(b) << endl;//4.2
	a.Relationship(b);//4.3
}