C++大学基础教程_7_4使用数组的范例

//_7_4_main_1.cpp

#include <iostream>
#include <iomanip>
using namespace std;

int main()
{
	cout << "Element" << setw(12) << "Value" << endl;

	//声明一个数组，然后用一个循环初始化数组
	int a[10];
	for(int i=0;i<10;i++)
		a[i] = 0;
	for(int j=0;j<10;j++)
		cout << "  a[" << j << "]" << setw(9) << a[j] << endl;
	cout << endl;
	
	//在声明中用初始化列表初始化数组
	int b[10] = {32,43,54,6,6,43,2,5,23,76};
	for(int j=0;j<10;j++)
		cout << "  b[" << j << "]" << setw(9) << b[j] << endl;
	cout << endl;

	//用常量变量指定一个数组大小，用计算结果设定数组元素
	const int arraySize = 10;//在声明变量常量的时候没有赋值是一个编译错误！！！！！！
	int s[arraySize];
	for(int i=0;i<10;i++)
		s[i] = 2*i + 1 ;
	for(int j=0;j<10;j++)
		cout << "  s[" << j << "]" << setw(9) << s[j] << endl;
	cout << endl;

	//求数组元素之和
	const int arraySize_1 = 10;
	int t[arraySize_1] = {87,68,96,100,23,54,5,65};
	int total = 0;
	for(int i=0;i<10;i++)
		total = total + t[i] ;//注意啊！！！！是 ' +t[i] ' ,不是' t[arraySize_1] ' !!!!!!!!!!!! 
	cout << "Total of array elements:" << total << endl;
	for(int j=0;j<10;j++)
		cout << "  t[" << j << "]" << setw(9) << t[j] << endl;
	

	system("pause >> cout");
	return 0;
}

 

//_7_4_main2.cpp
#include <iostream>
#include <iomanip>
#include <cstdlib>
#include <ctime>
using namespace std;

int main()
{
	//使用条形统计图表显示数组数据
	const int arraySize = 11;
	int s[arraySize] = {4,0,1,2,0,8,0,4,2,5,2};
	for(int i=0;i<arraySize;i++)
	{
		//输出“0-9 、10-19、20-29、、、、”
		if(i == 0)
			cout << "  0-9:" ;
		else if(i == 10)
			cout << "  100:" ;
		else
			cout << i*10 << "-" << i*10+9 << ":";
		for(int star=0;star<s[i];star++)
			cout << "*" ;
		cout << endl;
 	}
	
	cout << "\n\n" ;
	srand((unsigned)time(NULL));
	//使用数组汇总调查结果（40名学生评价学生食堂等级为1最差-10最好级）
	const int responseSize = 40;//学生投票的数组大小
	const int frequencySize = 11;//汇总的数组大小，表示每种结果（1-10）有多少人
	int response[responseSize];
	int frequency[frequencySize] = {0};
	for(int i=0;i<responseSize;i++)//随机数产生学生投票结果
		response[i] = 1 + rand()%10;
	cout << "response[]:" << endl;
	for(int i=0;i<responseSize;i++)
	{
		cout << setw(3) << response[i];
		if((i+1)%10 == 0)
			cout << endl;
	}
	//循环，计算每种评价出现的次数
	for(int answer=0;answer<responseSize;answer++)
	{
		frequency[response[answer]]++;//response[]最大可以达到10啊啊啊啊啊，所以responseSize为11
	}
	cout << "Reting" << setw(11) << "Frequency" << endl;
	for(int rating=1;rating<frequencySize;rating++)
		cout << setw(6) << rating << setw(11) << frequency[rating] << endl;
	
	//使用条形图统计
	for(int j=1;j<frequencySize;j++)
	{
		cout << setw(2) << j << ": " ;
		for(int count=0;count<frequency[j];count++)
			cout << "*" ;
		cout << endl;
	}
	
	system("pause >> cout");
	return 0;
}

 

_7_4_main3.cpp
//使用字符数组存储和操作字符串
//在下面的例子中如果第一次输入的是“hellothere”，那么最后还要再输入一次“there”
//如果第一次输入的是“hello there”，那么结果就会直接显现出来
//试试咯试试咯
#include <iostream>
using namespace std;
int main()
{
	char string1[20];
	char string2[] = "string literal";

	cout << "Enter the string \"Hello there\":";
	cin >> string1;
	cout << "string1 is :" << string1 << "\nstring2 is :" << string2 << endl;
	cout << "string1 with space between character is :" << endl;
	for(int i=0;string1[i]!='\0' ;i++)
		cout << " " << string1[i];
	cout << "\nstring2 with space between character is :" << endl;
	for(int i=0;string2[i]!='\0' ;i++)
		cout << " " << string2[i];
	cout << endl;
	cout << "enter \"there\" to string1: " ;
	cin >> string1;
	cout << "\nstring1 is :" << string1 << endl;
	system("pause >> cout");
	return 0;
}

//_7_4_main4.cpp
//static局部数组和自动局部数组
#include <iostream>
using namespace std;

void staticArrayInit(void);//定义static静态局部数组
void automaticArrayInit(void);//定义自动局部数组

int main()
{
	cout << "First call to each function:\n";
	staticArrayInit();
	automaticArrayInit();
	cout << "\n\nSecond call to each function:\n";
	staticArrayInit();
	automaticArrayInit();
	system("pause >> cout");
	return 0;
}

void staticArrayInit()
{
	static int array1[3];
	cout << "\nValues on entering staticArrayInit :\n";
	for(int i=0;i<3;i++)
		cout << "array1[" << i << "] = " << array1[i] << "  " ;
	cout <<"\nValues on exiting staticArrayInit :\n";
	for(int i=0;i<3;i++)
		cout << "array1[" << i << "] = " << (array1[i]+=5) << "  " ;//array1[i]+=5要加括号啊啊啊
	cout << endl;
}
void automaticArrayInit()
{
	int array2[]={1,2,3};
	cout << "\nValues on entering automaticArrayInit :\n";
	for(int i=0;i<3;i++)
		cout << "array2[" << i << "] = " << array2[i] << "  " ;
	cout <<"\nValues on exiting automaticArrayInit :\n";
	for(int i=0;i<3;i++)
		cout << "array2[" << i << "] = " << (array2[i]+=5) << "  " ;
	cout << endl;
}

 程序运行结果