C/C++程式語言教學用講義-鍾震璋 http://www.akey.idv.tw/course/cpp1.html

// ex.0-4
main(){
	char ch='a';
	printf("ch=%c\n",ch);
	printf("ch=%d\n",ch);
	printf("ch=%o\n",ch);
	printf("ch=%x\n",ch);
}

// ex.0-5
main(){
	int i=32, j=15;
	float f=12.3456;
	printf("i=%-4d",i);
	printf("j=%4d\n",j);
	printf("f=%f\n",f);
	printf("f=%e\n",f);
	printf("f=%6.2f\n",f);
}

// ex.0-6
main(){
	int a=155, b=9;
	float f;
	f=a/b;
	printf("a=%d, b=%d\n",a,b);
	printf("a/b=%f\n",a/b);
	printf("f=%f\n",f);
	printf("a/b=%f\n",(float)a/b);
}

// ex.0-7
main(){
	float f=123.59;
	int i=30;
	// find f-i and f/i, then output your answer!
}

// ex.0-8
main(){
	int a=15;
	printf("a=%d",a);
	printf("a in float is %f\n",a);
	printf("a in double is %e\n",a);
}

// ex.0-9
main(){
	int a,b;
	scanf("%d %d",&a, &b);
	printf("a+b=%d\n",a+b);
	printf("(a+b)/2=%.1f\n",(float)(a+b)/2);
}

// ex.0-10
main(){
	char ch;
	printf("Input a character:");
	scanf(" %c",&ch);
	printf("ch=%c, ASCII code is %d\n",ch,ch);
}

// ex.0-11
main(){
	char name[10];
	printf("What's your name:");
	scanf("%s",name);
	printf("Hi, %s, How are you?\n",name);
}

// ex.0-12
main(){
	int age;
	printf("Input your age: ");
	scanf("%d", &age);
	age=age+1;
	printf("Next year, you will be %d\n", age);
}

// ex.0-13
main(){
	int a, b;
	char ch='%';
	printf("First number: ");
	scanf("%d", &a);
	printf("Second number: ");
	scanf("%d", &b);
	printf("a+b=%d\n", a+b);
	printf("a-b=%d\n", a-b);
	printf("a*b=%d\n", a*b);
	printf("a/b=%f\n", (float)a/(float)b);
	printf("a%cb=%d\n", ch, a%b);
}

//ex.0-14
main(){
	if(5>2)
		printf("Return Value=%d\n",(5>2));
	if(1)
		printf("Happy Birthday!\n");
	if(0)
		printf("You are so king!\n");
}

//ex.0-15
main(){
	int i=3;
	printf("i=%d\n",i++);
	i=3;
	printf("i=%d\n",++i);
}

//ex.0-16
main(){
	int a,b;
	printf("First number: ");
	scanf("%d", &a);
	printf("Second number: ");
	scanf("%d", &b);
	if(a>0 && b>0)
		printf("a-b=%d\n",a-b);
	if(a-b<0 || a+b<0)
		printf("a+b=%d\n",a+b);
}

//ex.0-17
main(){
	int a,b;
	printf("First number: ");
	scanf("%d", &a);
	printf("Second number: ");
	scanf("%d", &b);
	printf("Before compute, a=%d\tb=%d\n",a,b);
	a+=b;
	printf("After compute, a=%d\tb=%d\n",a,b);
}

//ex.0-18
main(){
	int a,b;
	printf("First number: ");
	scanf("%d", &a);
	printf("Second number: ");
	scanf("%d", &b);
	printf("Before compute, a=%d\tb=%d\n",a,b);
	a-=b++;
	printf("After compute, a=%d\tb=%d\n",a,b);
}

//ex.0-19
//試寫一程式，將攝氏溫度轉成華氏溫度。
main(){
	int c;
	float f;
	printf("請輸入攝氏溫度：");
	scanf("%d", &c);
	f=9.0/5*c+32;
	printf("華氏溫度為%.2f度\n",f);
}

//ex.0-20
//試寫一轉換英哩為公里的程式。
//註：1英哩=1.6公里
main(){
	int mile;
	printf("請輸入英哩數：");
	scanf("%d", &mile);
	printf("你輸入的%d英哩，轉換成公里為%.2f公里\n", mile, 1.6*mile);
}

//ex.0-21
//試撰寫一程式，利用printf()函數，分別印出下列敘述的結果。
//1.將整數變數a的初始值設為10，整數變數b的初始值設為10；
//2.變數的值加1，b的值加5。
//3.將變數a加上b之後，將其平均，並將結果指定給整數變數c。
//4.將a的平方減去b的平方，指定給d。
main(){
	int a=20, b=10, d;
	float c;
	printf("1. a=%d, b=%d\n", a,b);
	a+=1;
	b+=5;
	printf("2. a=%d, b=%d\n", a, b);
	c=((float)a+=b)/2;
	printf("3. c=%f\n", c);
	d=a*a-b*b;
	printf("4. d=%d\n", d);
}

//ex.0-22
//已知圓球體積為4/3*pi*r*r*r，試寫一程式，輸入圓球半徑，經計算後輸出圓球體積。
main(){
	int r;
	float answer, pi=3.14159;
	printf("請輸入圓球半徑r=");
	scanf("%d", &r);
	answer=4.0/3*pi*r*r*r;
	printf("半徑為%d的圓球體積為%.2f\n", r, answer);
}


//ex.1-1
//結構化程式設計－循序性結構

main(){
	int a, b;
	printf("First number: ");
	scanf("%d", &a);
	printf("Second number: ");
	scanf("%d", &b);
	printf("(a+b)*(a-b)=%d\n", (a+b)*(a-b));
}

//ex.1-2
//結構化程式設計－選擇性結構

main(){
	int a, b;
	printf("First number: ");
	scanf("%d", &a);
	printf("Second number: ");
	scanf("%d", &b);
	if(a>b)
		printf("a-b=%d\n", a-b);
	printf("a*b=%d\n", a*b);
}

//ex.1-3
//結構化程式設計－迭代性結構

main(){
	int i;
	int sum=0;
	for(i=1; i<=10; i++) sum+=i;
	printf("1+2+3+...+10=%d\n", sum);
}

//ex.1-4
//擲骰子10000次，利用亂數取值，計算擲到點數為4的次數及機率。

main(){
	int i, count=0;
	for(i=1; i<=10000; i++)
		if((rand()%6+1)==4) count++;
	printf("擲10000次骰子時，出現4點的次數為%d次\n", count);
	printf("機率為%.3f\n", (float)count/10000);
}

//ex.1-5
//改用while迴圈
main(){
	int i, count=0;
	srand((unsigned)time(NULL));
	while(i<=10000){
		if((rand()%6+1)==4) count++;
		i++;
	}
	printf("擲10000次骰子時，出現4點的次數為%d次\n", count);
	printf("機率為%.3f\n", (float)count/10000);
}

//ex.1-6
//無窮迴圈

main(){
	int i;
	while(i != 0)
		printf("i=%d\n",i++);
}

//ex.1-7
//do while迴圈

main(){
	int n, i=1, sum=0;
	do{
		printf("Input n(n>0), It'll get result of 1+2+...+n= ");
		scanf("%d", &n);
	}while(n<=0);
	do{
		sum+=i++;
	while(i<=n);
	printf("1+2+...+%d=%d\n", n, sum);
}

//ex.1-8
//使用do while迴圈，計算n!

main(){
	int n, i=1, f=1;
	do{
		printf("Input n(n>0), It'll get result of n!: ");
		scanf("%d", &n);
	}while(n<=0);
	do
		f*=i++;
	while(i<=n);
	printf("%d!=%d\n", n, f);
}

//ex.1-9
//空迴圈

main(){
	int i;
	for(i=1; i<=10000; i++);
		printf("i=%d\n", i);
}

//ex.1-10
//巢狀迴圈(Nested Loops)
main(){
	int i, j;
	for(i=1; i<=9; i++){
		for(j=1; j<=9; j++)
			printf("%d*%d=%2d ",i ,j ,i*j);
		printf("\n");
	}
}


//ex.1-11: 巢狀迴圈，使用while敘述
main(){
	int i, j;
	while(i<=9){
		while(j<=9)
		{
			printf("%d*%d=%2d ",i,j,i*j);
			j++;
		}
		printf("\n");
		i++;
		j=1;
	}
	returen 0;
}

//ex.1-12: 以*符號列出一直角三角形
main(){
	int i,j,n=6;
	for(i=1;i<=n;i++){
		for(j=1;j<=i;j++)
			printf("*");
		printf("\n");
	}
}

//ex.1-13: 輸入一正整數, 將該正整數倒過來輸出
main(){
	int a,r;
	while(1){
		do
		{
			printf("Input an integer: ");
			scanf("%d", &a);
		} while(a<=0);
		printf("The answer is ");
		while(a!=0)
		{
			r=a%10;
			a/=10;
			printf("%d",r);
		}
		printf("\n\n");
	}
}

//ex.1-14: 迴圈跳離(break敘述)
main(){
	int i;
	for(i=1;i<=10;i++){
		if(i%3==0)
			break;
		printf("i=%d\n",i);
	}
	prinf("When loop interrupted, i=%d\n",i);
}

//ex.1-15: 迴圈跳離(continue敘述)
main(){
	int i;
	for(i=1;i<=10;i++){
		if(i%3==0)
			continue;
		printf("i=%d\n",i);
	}
	printf("When loop interrupted, i=%d\n",i);
}



//ex.1-16到ex.1-28為練習題，有程式設計上的問題，歡迎來信討論！


//ex.1-16
利用for迴圈寫一能產生如下圖之程式。
1
12
123
1234
12345

//ex.1-17
寫一程式產生如下圖之結果。
     *
    ***
   *****
  *******
 *********
***********

//ex.1-18
寫一程式，產生（由螢幕輸出）0~255之間的ASCII字元。

//ex.1-19
寫一程式，印出從3到100之間，所有可以被6整除的數值。

//ex.1-20
寫一程式，印出從1到1000之間，所有可以被7整除，又可被3整除的數值。

//ex.1-21
利用for迴圈，計算1+3+5+...+n之總和，其中n為奇數且由使用者輸入。

//ex.1-22
利用while迴圈，計算2+4+6+...+n之總和，其中n為偶數且由使用者輸入。

//ex.1-23
試寫一程式，印出1到100之間所有整數的平方值，最後再印出這些平方值的總和。

//ex.1-24
假設有一條繩子長3000公尺，每天剪去一半的長度，請問需要花費幾天的時間，繩子的長度會短於5公尺？

//ex.1-25
試利用do while迴圈，計算1!+2!+3!+...+n!的總和，其中n由使用者輸入。

//ex.1-26
計算1^2-2^2+3^3-4^2+...+47^2-48^2+49^2-50^2的總和。(說明：1^2代表1的平方，而2^2代表2的平方，以此類推)

//ex.1-27
計算1+1/2+1/3+...+1/n之總和，其中n由使用者輸入。

//ex.1-28
計算1+1/1!+1/2!+1/3!+...+1/n!之總和，其中n由使用者輸入。


//ex.2-1
main(){
	int a,b;
	printf("first number:");
	scanf("%d",&a);
	printf("second number:");
	scanf("%d",&b);
	if (a>b){
		printf("a+b=%d\n",a+b);
		printf("a-b=%d\n",a-b);
	}
	printf("a*b=%d\n",a*b);
}

//ex.2-2: if-else敘述
main(){
	int a,b;
	printf("first number:");
	scanf("%d",&a);
	printf("second number:");
	scanf("%d",&b);
	if (a>b){
		printf("a-b=%d\n",a-b);
		printf("a%%b=%d\n",a%b);
	}
	else{
		printf("a+b=%d\n",a+b);
		printf("a*b=%d\n",a*b);
	}
}

//ex.2-3
main(){
	int a;
	printf("Input a number:");
	scanf("%d",&a);
	if (a%2==1)
		printf("%d is a odd number\n",a);
	else
		printf("%d is a even number\n",a);
}

//ex.2-4: 巢狀if敘述
main(){
	int a,b;
	printf("First number(a):");
	scanf("%d",&a);
	printf("Second number(b):");
	scanf("%d",&b);
	if (a>0)
		if (b>0)
			printf("a-b=%d\n",a-b);
		else
			printf("a+b=%d\n",a+b);
}

//ex.2-5: else-if敘述
main(){
	int score;
	printf("Your score:");
	scanf("%d",&score);
	if (score>=80)
		printf("%d is A\n",score);
	else if (score>=70)
			printf("%d is B\n",score);
		else if (score>=60)
				printf("%d is C\n",score);
			else
				printf("Failed!!\n");
}

//ex.2-6
main(){
	int a,b;
	printf("First number:");
	scanf("%d",&a);
	printf("Second number:");
	scanf("%d",&b);

	if (a>b)
		if (a-b>6)
			printf("%d%%%d=%d\n",a,b,a%b);
		else
			printf("%d*%d=%d\n",a,b,a*b);
}

//ex.2-7
main(){
	int a,b;
	printf("First number:");
	scanf("%d",&a);
	printf("Second number:");
	scanf("%d",&b);
	if (a>b){
		if (a-b>6)
			printf("%d%%%d=%d\n",a,b,a%b);
	}
		else
			printf("%d*%d=%d\n",a,b,a*b);
}

//ex.2-8: 條件運算子?:
main(){
	int i,n,a,max,min;
	max=-32768;
	min=32767;

	printf("How many numbers do you want to input: ");
	scanf("%d",&n);

	for(i=1;i<=n;i++){
		printf("Input number %d: ",i);
		scanf("%d",&a);
		max=(a>max)?a:max;
		min=(a<min)?a:min;
	}
	printf("The maximum number is %d\n",max);
	printf("The minimum number is %d\n",min);
}

//ex.2-9: switch-case敘述與break敘述
main(){
	int a,b,i,ans=1;
	char oper;
	printf("Input an expression(example:3+2): ");
	scanf("%d %c %d",&a,&oper,&b);
	switch (oper){
		case '+':
			printf("%d+%d=%d\n",a,b,a+b);
			break;
			case '-':
			printf("%d-%d=%d\n",a,b,a-b);
			break;
		case '*':
			printf("%d*%d=%d\n",a,b,a*b);
			break;
		case '/':
			printf("%d/%d=%.3f\n",a,b,(float)a/b);
			break;
		case '%':
			printf("%d%%%d=%d\n",a,b,a%b);
			break;
		case '^":
			for(i=1;i<=b;i++)
				ans*=a;
			printf("%d^%d=%d",a,b,ans);
			break;
		default:
			printf("Unknown expression!!\n");
	}
}

//ex.2-10
main(){
	int i,count1,count2,count3,count4,count5,count6;
	count1=count2=count3=count4=count5=count6=0;
	srand((unsigned)time(NULL));
	for(i=1;i<=10000;i++){
		switch((rand()%6+1))
		{
			case 1: count1++;
					break;
			case 2: count2++;
					break;
			case 3: count3++;
					break;
			case 4: count4++;
					break;
			case 5: count5++;
					break;
			case 6: count6++;
		}
	}
	printf("擲10000次骰子時\n");
	printf("出現1點的次數為%d次\n",count1);
	printf("出現2點的次數為%d次\n",count2);
	printf("出現3點的次數為%d次\n",count3);
	printf("出現4點的次數為%d次\n",count4);
	printf("出現5點的次數為%d次\n",count5);
	printf("出現6點的次數為%d次\n",count6);
}

//ex.2-11
main(){
	char grade;
	printf("Input grade:");
	scanf("%c",&grade);
	switch(grade){
		case 'a':
		case 'A':
			printf("Excellent!\n");
			break;
		case 'b':
		case 'B':
			printf("Good!\n");
			break;
		case 'c':
		case 'C':
			printf("Be study hard!\n");
			break;
		default:
			printf("Failed!\n");
	}
}

//ex.2-12: 使用switch-case敘述計算擲出不同點數的次數(累加效果)
main(){
	int i,count1,count2,count3,count4,count5,count6;
	count1=count2=count3=count4=count5=count6=0;
	srand((unsigned)time(NULL));
	for(i=1;i<=10000;i++){
		switch((rand()%6+1))
		{
			case 1:count1++;
			case 2:count2++;
			case 3:count3++;
			case 4:count4++;
			case 5:count5++;
			case 6:count6++;
		}
	}
	printf("擲10000次骰子時\n");
	printf("出現1點的次數為%d次\n",count1);
	printf("出現2點的次數為%d次\n",count2);
	printf("出現3點的次數為%d次\n",count3);
	printf("出現4點的次數為%d次\n",count4);
	printf("出現5點的次數為%d次\n",count5);
	printf("出現6點的次數為%d次\n",count6);
}

//ex.2-13: 使用goto敘述
main(){
	int i=0,sum=0;

mylable:
	sum+=++i;
	printf("%d",i);
	if (i<10){
		printf("+");
		goto mylable;
	}
	printf("=%d\n",sum);
}

//ex.2-14: 試撰寫一程式，輸入三個整數，判斷這三個整數是否能構成三角形的三個邊長。（註:兩邊長之和必須大於第三邊）

//ex.2-15: 試撰寫一程式，輸入三個整數值，求最大值及最小值，再將三個整數的平均值輸出。

//ex.2-16: 試撰寫一程式，輸入15個學生的成績，成績在0~59分為C，60~75分為B，76~100分為A，輸入完畢後，將得到A、B、C的人數印出。

//ex.2-17: 假設某便利商店的工讀生的月薪資，可以依照下列方式計算：
		0~60個小時，每小時75元
		61~75個小時，以1.25倍計算
		76個小時以後以1.75倍計算
　　　　　　試撰寫一程式，輸入某工讀生該月的工作時數，然後計算其實領的薪資。

//ex.2-18: 試利用if敘述，將輸入的學生成績依下列的分類方式分級。
		00~59：E級
		60~69：D級
		70~79：C級
		80~89：B級
		90~100：A級

//ex.2-19: 利用亂數取得100個0~1000的整數，並於程式中判斷這些整數為奇數還是偶數，並將奇數與偶數的總個數輸出。

//ex.2-20: 試撰寫一程式，輸入x、y座標值，判斷該點位於那一個象限或是座標軸上。舉例來說，若輸入的座標值為(3.0,-2.5)，輸出即為第四象限；若輸入的座標值為(4.5,0.0)，則輸出即為x軸。

//ex.2-21: 簡單函數
void star();
main(){
	int i;
	printf("Input an integer:");
	scanf("%d",&i);
	star();
	printf("%d*%d=%d\n",i,i,i*i);
	star();
}
void star(){
	int j;
	for(j=1;j<=8;j++)
		printf("*");
	printf("\n");
}

//ex.2-22: 求絕對值
int abs(int);
main(){
	int i;
	printf("Input an integer:");
	scanf("%d",&i);
	printf("│%d│=%d\n",i,abs(i));
}
int abs(int a){
	if (a<0) return -a;
	else return a;
}

//ex.2-23: 呼叫自訂函數與區域變數
void func(int,int);
main(){
	int a=3,b=6;
	printf("In main(),a=%d,b=%d\n",a,b);
	func(a,b);
	printf("After func(),a=%d,b=%d\n",a,b);
}
void func(int a,int b){
	a+=10;
	b+=10;
	printf("In func(),a=%d,b=%d\n",a,b);
}

//ex.2-24: 傳回較大值
int max(int,int);
main(){
	int a,b;
	printf("First number:");
	scanf("%d",&a);
	printf("Second number:");
	scanf("%d",&b);
	printf("The larger number is %d\n",max(a,b));
}
int max(int i,int j){
	if (i>j) return i;
	else return j;
}

//ex.2-25: 最大公因數
int gcd(int,int);
main(){
	int a,b;
	printf("First number:");
	scanf("%d",&a);
	printf("Second number:");
	scanf("%d",&b);
	printf("The GCD of %d and %d is %d\n",a,b,gcd(a,b));
}
int gcd(int i,int j){
	int g;
	while(j!=0){
		g=i%j;
		i=j;
		j=g;
	}
	return i;
}

//ex.2-26: 沒有傳回值的函數
void myprint(int,char);
main(){
	int a;
	char ch;
	printf("Input a character:");
	scanf("%c",&ch);
	printf("How many times do you want to print? ");
	scanf("%d",&a);
	myprint(a,ch);
	printf("Printed!!\n");
}
void myprint(int n,char c){
	int i;
	for(i=1;i<=n;i++)
		putchar(c);
	printf("\n",c);
}

//ex.2-27: 區域變數
void func();
main(){
	auto int a=100;
	printf("In Main(),a=%d\n",a);
	func();
	printf("In Main(),a=%d\n",a);
}
void func(){
	int a=300;
	printf("In func(),a=%d\n",a);
}

//ex.2-28: 區域靜態變數
void func();
main(){
	func();
	func();
	func();
}
void func(){
	static int a=100;
	printf("In func(),a=%d\n",a);
	a+=200;
}

//ex.2-29: 暫存器變數
main(){
	time_t start,end;
	register int i,j;
	start=time(NULL);
	for(i=1;i<=50;i++){
		for(j=1;j<=50;j++)
			printf("%2d*%2d=%4d\t",i,j,i*j);
		printf("\n");
	}
	end=time(NULL);
	printf("It's spends %.1f seconds\n",difftime(end,start));
}

//ex.2-30: 呼叫多個函數
void sum(int),fact(int);
main(){
	int a=5;
	fact(a);
	sum(a);
}
void fact(int a){
	int i,total;
	for(i=1,total=1;i<=a;i++)
		total*=i;
	printf("1*2*...*%d=%d\n",a,total);
}

void sum(int a){
	int i,sum;
	for(i=1,sum=0;i<=a;i++)
		sum+=i;
	printf("1+2+...+%d=%d\n",a,sum);
}

//ex.2-31: 相互呼叫函數
void sum(int);
void fact(int);
main(){
	int a=5;
	fact(a);
	sum(a+5);
}
void fact(int a){
	int i,total;
	for(i=1,total=1;i<=a;i++) total*=i;
	printf("1*2*...*%d=%d\n",a,total);
	sum(a);
}
void sum(int a){
	int i,sum;
	for(i=1,sum=0;i<=a;i++) sum+=i;
	printf("1+2+...+%d=%d\n",a,sum);
}

//ex.2-32: 遞迴(Recursion)函數
int fact(int);
main(){
	int a;
	do{
		printf("Input an integer:");
		scanf("%d",&a);
	} while (a<0);
	printf("1*2*...*%d=%d\n",a,fact(a));
}
int fact(int a){
	if(a>0) return (a*fact(a-1));
	else return 1;
}

//ex.2-33: 計算次方
int power(int,int);
main(){
	int a=2,b=3;
	printf("%d^%d=%d\n",a,b,power(a,b));
}
int power(int a,int b){
	if(b==0) return 1;
	else return (a*power(a,b-1));
}

//ex.2-34: 費氏數列(Fibonacci Sequence)
int fib(int);
main(){
	int n;
	for(n=1;n<=10;n++)
		printf("%d ",fib(n));
}
int fib(int n){ /*自訂函數fib()，計算費氏數列的第n個數*/
	if(n==1 || n==2) return 1;
	else return (fib(n-1)+fib(n-2));
}

//ex.2-35: 試寫一函數 void kitty()，當主程式呼叫 kitty()時，螢幕上會顯示出 "Hello Kitty" 之字串。

//ex.2-36: 寫一函數 void kitty(int k)，當主程式呼叫kitty(k) 時，螢幕上會顯示出k行的 "Hello Kitty"。

//ex.2-37: 寫一函數 int cub(int x)，其作用為傳回引數 x 的 3 次方。

//ex.2-38: 試寫一函數int mod(int x,int y)，來計算x/y的商數及餘數。

//ex.2-39: 利用ex.2-33的power()函數，其引數及傳回值型態皆為整數，現在，試寫一函數pow(x,n)來計算 ，其中x為浮點數，n為正整數，而傳回值為浮點數。例如，pow(5.0,2)=25.0。

//ex.2-40: 利用ex.2-30中所定義的函數fact(n)來計算下列方程式的值。
	1/1!+1/2!+1/3!+...+1/10!

//ex.3-1: 一維陣列的輸入與輸出
main(){
	int i,score[5];
	for(i=0;i<=4;i++){
		printf("Input score:");
		scanf("%d",&score[i]);
	}
	printf("***Output***\n");
	for(i=0;i<=4;i++)
		printf("score[%d]=%d\n",i,score[i]);
}

//ex.3-2: 比較陣列元素值的大小
main(){
	int A[5]={74,48,30,17,62};
	int i,min,max;
	min=max=A[0];
	printf("elements in array A are ");
	for(i=0;i<5;i++){
		printf("%d  ",A[i]);
		if(A[i]>max)
			max=A[i];
		if(A[i]<min)
			min=A[i];
	}
	printf("\nMaximum is %d",max);
	printf("\nMinimum is %d\n",min);
}

//ex.3-3: 未知元素個數的陣列
#define MAX 100
main(){
	int score[MAX];
	int i=0,num;
	float sum=0.0f;
	printf("Enter 0 stopping input!!\n");
	do{
		printf("Input score:");
		scanf("%d",&score[i]);
	}while(score[i++]>0);
	num=i-1;
	for(i=0;i<num;i++)
		sum+=score[i];
	printf("Average of all is %.2f\n",sum/num);
}

//ex.3-4: 陣列的搜尋
#define SIZE 6
main(){
	int i,num,flag=0;
	int A[SIZE]={33,75,69,41,33,19};
	printf("Input an integer to search:");
	scanf("%d",&num);
	printf("elements in array A(0~5): ");
	for(i=0;i<SIZE;i++)
		printf("%d ",A[i]);
	for(i=0;i<SIZE;i++)
		if(A[i]==num)
		{
			printf("\nYes! A[%d]=%d",i,A[i]);
			flag=1;
		}
	if(flag == 0)
		printf("\nNot found!!\n");
}

//ex.3-5: 二維陣列的輸入與輸出
main(){
	int i,j,sale[2][4],sum=0;
	for(i=0;i<2;i++)
		for(j=0;j<4;j++)
		{
			printf("業務員%d的第%d季業績:",i+1,j+1);
			scanf("%d",&sale[i][j]);
		}
	printf("***Output***");
	for(i=0;i<2;i++){
		printf("\n業務員%d的業績分別為",i+1);
		for(j=0;j<4;j++)
		{
			printf("%d  ",sale[i][j]);
			sum+=sale[i][j];
		}
	}
	printf("\n2001年總銷售量為%d部車\n",sum);
}

//ex.3-6: 轉置矩陣
main(){
	int i,j,matrx[4][4]={{1,2,3,4},{5,6,7,8},{9,10,11,12},{13,14,15,16}};
	printf("elements in array:\n");
	for(i=0;i<4;i++){
		for(j=0;j<4;j++)
			printf("%4d",matrx[i][j]);
		printf("\n");
	}
	printf("\nafter reversed:\n");
	for(j=0;j<4;j++){
		for(i=0;i<4;i++)
			printf("%4d",matrx[i][j]);
		printf("\n");
	}
}

//ex.3-7: 多維矩陣
main(){
	int A[2][2][2]={{{95,85},{66,78}},{{89,77},{60,83}}};
	int i,j,k,sum=0;

	for(i=0;i<2;i++)
		for(j=0;j<2;j++)
			for(k=0;k<2;k++)
			{
				printf("A[%d][%d][%d]=%d\n",i,j,k,A[i][j][k]);
				sum+=A[i][j][k];
			}
	printf("sum=%d\n",sum);
}

//ex.3-8: 傳遞陣列給函數
#define SIZE 4
void addarr(int b[]),print_matrix(int B[]);
main(){
	int A[SIZE]={0};
	printf("Before process...\n");
	print_matrix(A);
	addarr(A);
	printf("\nAfter process...\n");
	print_matrix(A);
}
void print_matrix(int B[]){
	int i;
	printf("elements in array:");
	for(i=0;i<SIZE;i++)
		printf("%d ",B[i]);
	printf("\n");
}
void addarr(int B[]){
	int i;
	for(i=0;i<SIZE;i++) B[i]+=3;
	printf("\nIn function addarr(),\n");
	print_matrix(B);
}

//ex.3-9: 計算矩陣中的奇數及偶數個數
#define SIZE 10
void print_matrix(int a[]),count(int a[]);
main(){
	int data[SIZE]={61,46,78,47,40,31,8,21,93,71};
	printf("elements in array:");
	print_matrix(data);
	count(data);
}
void print_matrix(int a[]){
	int i;
	for(i=0;i<SIZE;i++)
		printf("%d ",a[i]);
	printf("\n");
}
void count(int a[]){
	int i,cnt1=0,cnt2=0;
	for(i=0;i<SIZE;i++)
		if(a[i]%2==1) cnt1++;
		else cnt2++;
	printf("There are %d odd and %d even numbers\n",cnt1,cnt2);
}

//ex.3-10: 反轉一維矩陣內的值
#define SIZE 10
void print_matrix(int a[]),convert(int a[]);
main(){
	int data[SIZE]={1,2,3,4,5,6,7,8,9,10};
	printf("Before process...\n");
	print_matrix(data);
	convert(data);
	printf("After process...\n");
	print_matrix(data);
}
void print_matrix(int a[]){
	int i;
	for(i=0;i<SIZE;i++)
		printf("%d ",a[i]);
	printf("\n");
}
void convert(int a[]){
	int i,j,b[SIZE];
	for(i=0,j=SIZE-1;i<SIZE,j>=0;i++,j--) b[j]=a[i];
	for(i=0;i<SIZE;i++) a[i]=b[i];
}

//ex.3-11: 氣泡排序法(Bubble Sort)
#define SIZE 5
void print_matrix(int a[]),bubble(int a[]);
main(){
	int data[SIZE]={63,52,17,6,81};
	printf("Before process...\n");
	print_matrix(data);
	bubble(data);
	printf("After process...\n");
	print_matrix(data);
}
void print_matrix(int a[]){
	int i;
	for(i=0;i<SIZE;i++)
		printf("%d ",a[i]);
	printf("\n");
}
void bubble(int a[]){
	int i,j,temp;
	for(i=1;i<SIZE;i++)
		for(j=0;j<(SIZE-1);j++)
			if(a[j]>a[j+1]){
				temp=a[j];
				a[j]=a[j+1];
				a[j+1]=temp;
			}
}

//ex.3-12: 印出變數位址
void func(int);
main(){
	int a=39;
	printf("In main(),a=%d,address=%p\n",a,&a);
	func(a);
}
void func(int a){
	printf("In func(),a=%d,address=%p\n",a,&a);
}

//ex.3-13: 印出陣列位址
void func(int *);
main(){
	int i,a[4]={22,81,31,66};
	printf("In main(),\n");
	for(i=0;i<4;i++)
		printf("a[%d]=%2d,address=%p\n",i,a[i],&a[i]);
	func(a);
}

void func(int b[]){
	int i;
	printf("In func(),\n");
	for(i=0;i<4;i++)
		printf("b[%d]=%2d,address=%p\n",i,b[i],&b[i]);
}

//ex.3-14: 假設某一公司有五種產品A、B、C、D與E，其單價分別為12、16、10、14與15元；而該公司共有三位銷售員，他們在某個月份的銷售量如下所示。

銷售員	產品A	產品B	產品C	產品D	產品E
1	33	32	56	45	33
2	77	33	68	45	43
3	43	55	34	67	65

試寫一程式來計算：
1.每一個銷售員的銷售總金額。
2.每一項產品的銷售總金額。
3.有最好業績（銷售總金額為最多者）的銷售員。
4.銷售總金額為最多的產品。

//ex.3-15: 試撰寫一程式，由鍵盤輸入20個浮點數到陣列存放，並計算其平均值。

//ex.3-16: 試設計一程式，將字串陣列中的所有小寫字母轉換成大寫字母。

//ex.3-17: 印出字元長度及字串長度
main(){
	char a[]="My friend";
	char b='c';
	char str[]="c";
	printf("sizeof(a)=%d\n",sizeof(a));
	printf("sizeof(b)=%d\n",sizeof(b));
	printf("sizeof(str)=%d\n",sizeof(str));
}

//ex.3-18: 輸入及印出字串
main(){
	char name[15];
	int i;
	for(i=0;i<2;i++){
		printf("What's your name?");
		scanf("%s",name);
		printf("Hi! %s,How are you?\n\n",name);
	}
}

//ex.3-19: 輸入及輸出字串
main(){
	char name[15];
	puts("What's your name?");
	gets(name);
	puts("Hi!");
	puts(name);
	puts("How are you?");
}

//ex.3-20: 字串陣列
main(){
	char name[3][10]={"Anress Jong","Marchman","Jojo Lin"};
	int i;
	for(i=0;i<3;i++)
		printf("name[%d]=%s\n",i,name[i]);
	printf("\n");
	for(i=0;i<3;i++){
		printf("address of name[%d]=%p\n",i,&name[i]);
		printf("address of name[%d][0]=%p\n\n",i,&name[i][0]);
	}
}

//ex.3-21: 字串陣列
main(){
	char students[3][10];
	int i;
	for(i=0;i<3;i++){
		printf("Input student%d's name:",i);
		gets(students[i]);
	}
	puts("***OutPut***");
	for(i=0;i<3;i++)
		printf("students[%d]=%s\n",i,students[i]);
}

//ex.3-22: 字串陣列的複製
#define MAX 3
#define LENGTH 10
main(){
	char students[MAX][LENGTH]={"Anress Jong","Marchman","Jojo Lin"};
	char copystr[MAX][LENGTH];
	int i,j;
	for(i=0;i<MAX;i++){
		for(j=0;j<LENGTH;j++)
			if(students[i][j]=='\0') break;
			else copystr[i][j]=students[i][j];
		copystr[i][j]='\0';
	}
	for(i=0;i<MAX;i++)
		printf("copystr[%d]=%s\n",i,copystr[i]);
}

//ex.3-23: 小寫轉換成大寫
#define SIZE 3
#define LENGTH 12
void convert();
main(){
	int i;
	char a[SIZE][LENGTH]={"Bloodshed","Dev c++","Program20"};
	printf("Before process..\n");
	for(i=0;i<SIZE;i++)
		printf("a[%d]=%s\n",i,a[i]);
	convert(a);
	printf("\nAfter process..\n");
	for(i=0;i<SIZE;i++)
		printf("a[%d]=%s\n",i,a[i]);
}

void convert(char m[SIZE][LENGTH]){
	int i,j;
	for(i=0;i<SIZE;i++)
		for(j=0;j<LENGTH;j++)
			if(m[i][j]=='\0') break;
			else if((m[i][j]>=97) && (m[i][j]<=122)) m[i][j]-=32;
}