1. Lecture 7: Structure and Class
solving quadric equations as an example
class
air-plane and bullets.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

2. CS3369 Real Time Control Software/Wang Lusheng
Computing the roots of a quadric equation
The roots of a quadric equation ax2+bx+c=0 are
x1= (-b+( b2-4ac))/2ac
x2=x1= (-b- ( b2-4ac))/2ac
#include<iostream.h>
float x1, x2;
int flag=0;
void roots(float a, float b, float c)
void main(void) {
roots(1.0,2.0, 1.0);
if(flag == 0)
cout<<“The roots are”<<x1<<x2;
else
cout<<“No real root”; }
void roots(float a, float b, float c) {
if (b*b-4*a*c>=0)
x1=(-b+sqrt(b*b-4*a*c))/(2*a*c);
x2 =(-b-sqrt(b*b-4*a*c))/(2*a*c); }
else
flag=1;
x1, x2 and flag are used as global variables. Otherwise, function roots must return two values (we do not know how to do it.)
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

3. CS3369 Real Time Control Software/Wang Lusheng
Define structures
Structures are aggregate data types built using elements of other types.
We can use structure to group several variables together
struct two_roots {
float x1;
float x2;
} r;
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

4. Define a function of two_roots type
The function roots returns a value of type two_roots that contains two values of type float.
struct two_roots roots (float a, float b, float c)
{ struct two_roots r;
if (b*b-4*a*c>=0)
{ r.x1=(sqrt (b*b-4*a*c)-b)/(2*a*c);
r.x2=(-sqrt(b*b-4*a*c)-b)/(2*a*c);}
else
x3=100;
return r; }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

5. Using structures in main()
In main function, we can print the two roots as follows;
#include <iostream.h>
int x3;
struct two_roots {
float x1;
float x2; };
struct two_roots roots (float a, float b, float c);
void main(void)
{ struct two_roots z;
z=roots(1.0, 2.0, 1.0);
if (x3==100)
cout<<“There is no real root”;
else
cout<<“The roots are”<< z.x1<<“ ”<<z. x2; }
struct two_roots roots (float a, float b, float c)
{ struct two_roots r;
if (b*b-4*a*c>=0)
{ r.x1=(sqrt (b*b-4*a*c)-b)/(2*a*c);
r.x2=(-sqrt(b*b-4*a*c)-b)/(2*a*c); }
else
x3=100;
return r;
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

6. CS3369 Real Time Control Software/Wang Lusheng
Time Services (Clock)
struct the_time {int hrs, int mins, int secs, int hundth;};
struct the_time get_time() {
the_time tmp;
int i,j,k,l;
_AH=0x2C; //service 0x2C for get time
interrupt(0x21); //interrupt 0x21
i=_CH; j=_CL; k=_DH; l=_DL;
tmp.hrs=i; tmp.mins=j; tmp.secs=k; tmp.hundth=l;
return tmp; }
void main()
{ struct the_time x;
x=get_time();
cout<<“The hour is ”<<x.hrs<<“The minute is ”<<x.mins;
cout<<“The second is ”<<x.sees;
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

7. Problem Solving: Student Records
We define a structure that can hold student records
structure student {
char name[20];
int student_id;
char grade; };
struct student x;
void main()
{int j;
cout<<“Please enter your name with <=20 characters\n”;
for(j=0; j<=19; j++)
cin>>x.name[j];
cout<<“Please enter your student number\n”;
cin>>x.student_id;
cout<<“Please enter the grade (A, B, C, D, F) \n”;
cin>>x.grade;
} Question: How to print out those input records?
The program asks
users to enter a
record of
students. Each
record contains
the name,
student_id and
grade.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

8. Problem Solving: Student Records
We define a structure that can hold student records
structure student {
char name[20];
int student_id;
char grade; };
struct student x[56];
void main()
{int i,j;
for(i=0; i<=55; i++)
{ cout<<“Please enter your name with <=20 characters\n”;
for(j=0; j<=19; j++)
cin>>x[i].name[j];
cout<<“Please enter your student number\n”;
cin>>x[i].student_id;
cout<<“Please enter the grade (A, B, C, D, F) \n”;
cin>>x[i].grade;
} Question: How to print out those input records?
The program asks
users to enter 104
records of
students. Each
record contains
the nemae,
student_id and
grade.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

9. CS3369 Real Time Control Software/Wang Lusheng
Classes
Classes enable the programmer to model objects that have attributes (represented as data members) and behaviors or operations (represented as member functions).
Object-oriented programming models real-world objects with software counterparts--classes
Objects of the same class have the same characteristics
e.g., cars, vehicles, air-planes, etc.
OOP encapsulates data (attribute) and functions (behavior) into packages called objects.
Objects have the property of information hiding.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

10. CS3369 Real Time Control Software/Wang Lusheng
Classes (continued)
information hiding : objects may know how to communicate with each other, but do not know how other objects are implemented.
We can build software by combining “standardized, interchangeable parts” --classes.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

11. Define air-plane as a class
void main(void) {
int driver = DETECT,mode;
int i,k,f=0,f3=0;
char x;
Air y1, y2, y3;
initgraph(&driver,&mode,"a:\\bgi");
setcolor(WHITE);
line(1,400,400,400);
for ( i = 0; i < 80; i++ )
setcolor(BLUE); y1.size=2; y1.planeshow(5*i, 5);
x=read_key();
if (x =='u') f=f-8;
if (x =='i') f=f+8;
if (x=='o') f3=f3-8;
if (x=='p') f3=f3+8;
setcolor(YELLOW); y2.size=4; y2.planeshow(5*(i-8), f);
setcolor(RED); y3.size=6;y3.planeshow(5*(i-16), f3);
delay (300);
y1.ereasep(5*i, 5); y2.ereasep(5*(i-8), f);
y3.ereasep(5*(i-16), f3); }
closegraph();
#include <graphics.h>
#include<dos.h>
#include<iostream.h>
#include<conio.h>
class Air{
public:
int size;
void planeshow(int i,int k);
void ereasep(int i, int k);
/*i decides the herizontal position */
/* k decides the vertical position */ };
void Air::planeshow(int i,int k) {
int j;
circle(i+5, 200+size+k, size);
circle(i+3, 200+2*size+k, size);
for (j=0; j<=4+3*size; j=j+size)
circle(i+j, 200+k, size);
circle(i+5, 200-size+k, size);
circle(i+3, 200-2*size+k, size); }
void Air::ereasep(int i, int k) {
int j;
setcolor(BLACK);
circle(i+5, 200+size+k, size);
circle(i+3, 200+2*size+k, size);
for (j=0; j<=4+3*size; j=j+1)
circle(i+j, 200+k, size);
circle(i+5, 200-size+k, size);
circle(i+3, 200-2*size+k, size); }
char read_key()
{ int y=1;
char x;
_AH=0x01;
geninterrupt(0x16);
y=_FLAGS&0x40;
if(y == 0)
_AH=0x00;
x=_AL;
return x; }
return '?';
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

12. Define air-plane as a class
void main(void) {
int driver = DETECT,mode;
int sf=0, i,k,f=0,f3=0;
char x;
Air y1, y2, y3;
initgraph(&driver,&mode,"a:\\bgi");
setcolor(WHITE);
line(1,400,400,400);
for ( i = 0; i < 120; i++ )
setcolor(BLUE); y1.size=2; y1.planeshow(5*i, 5);
x=read_key();
if (x =='u') f=f-8;
if (x =='i') f=f+8;
if (x=='o') f3=f3-8;
if (x=='p') f3=f3+8;
setcolor(YELLOW); y2.size=3; y2.planeshow(5*(i-8), f);
setcolor(RED); y3.size=3;
y3.planeshow(5*(i-16), f3);
if(x=='k'){sf=1; y2.shoot(5*(i-8), f);}
if (sf==0) delay (300);
else sf=0;
y1.ereasep(5*i, 5); y2.ereasep(5*(i-8), f);
y3.ereasep(5*(i-16), f3); }
closegraph();
#include<dos.h>
#include <graphics.h>
#include<iostream.h>
#include<conio.h>
class Air{
public:
int size;
void planeshow(int i,int k);
void ereasep(int i, int k);
void shoot(int i, int k); };
void Air::planeshow(int i,int k) {
int j;
circle(i+5, 200+size+k, size);
circle(i+3, 200+2*size+k, size);
for (j=0; j<=4+3*size; j=j+size)
circle(i+j, 200+k, size);
circle(i+5, 200-size+k, size);
circle(i+3, 200-2*size+k, size); }
void Air::ereasep(int i, int k)
setcolor(BLACK);
for (j=0; j<=4+3*size; j=j+1)
void Air::shoot(int i, int k)
{int j; sound(700);
for(j=0; j<=10; j++) {
setcolor(RED); line(i+j*30, 200+k,i+j*30+18, 200+k );
delay (30);
setcolor(BLACK); line(i+j*30, 200+k,i+j*30+18, 200+k); }
nosound();
char read_key()
{ int y=1;
char x;
_AH=0x01;
geninterrupt(0x16);
y=_FLAGS&0x40;
if(y == 0)
_AH=0x00;
x=_AL;
return x; }
return '?';
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

13. Define air-plane and Shoot classes
void Air::ereasep(int i, int k) {
int j;
setcolor(BLACK);
circle(i+5, 200+size+k, size);
circle(i+3, 200+2*size+k, size);
for (j=0; j<=4+3*size; j=j+1)
circle(i+j, 200+k, size);
circle(i+5, 200-size+k, size);
circle(i+3, 200-2*size+k, size); }
void Air::shoot(int i, int k)
{int j; sound(700);
for(j=0; j<=10; j++)
setcolor(RED); line(i+j*30, 200+k,i+j*30+18, 200+k ); delay (30);
setcolor(BLACK); line(i+j*30, 200+k,i+j*30+18, 200+k);
nosound();
#include<dos.h>
#include <graphics.h>
#include<iostream.h>
#include<conio.h>
class Air{
public:
int size;
void planeshow(int i,int k);
void ereasep(int i, int k);
void shoot(int i, int k);
/*i decides the herizontal position */
/* k decides the vertical position */ };
void Air::planeshow(int i,int k) {
int j;
circle(i+5, 200+size+k, size);
circle(i+3, 200+2*size+k, size);
for (j=0; j<=4+3*size; j=j+size)
circle(i+j, 200+k, size);
circle(i+5, 200-size+k, size);
circle(i+3, 200-2*size+k, size); }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

14. Define air-plane and Shoot classes
void main(void) {
int driver = DETECT,mode;
int sf=0, i,k,f=0,f3=0, xi=0, yi=0;
char x;
Air y1, y2, y3;
Shoot bullet;
initgraph(&driver,&mode,"a:\\bgi");
setcolor(WHITE);
line(1,400,400,400);
for ( i = 0; i < 80; i++ )
setcolor(BLUE); y1.size=2; y1.planeshow(5*i, 5);
x=read_key();
if (x =='u') f=f-8;
if (x =='i') f=f+8;
if (x=='o') f3=f3-8;
if (x=='p') f3=f3+8;
setcolor(YELLOW); y2.size=3; y2.planeshow(5*(i-8), f);
if(x=='k'){sf=1; y2.shoot(5*(i-8), f);}
setcolor(RED); y3.size=3;y3.planeshow(5*(i-16), f3);
bullet.point(xi,yi);
if(x=='l') bullet.sh(xi,yi);
if (sf==0) delay (300);
else sf=0;
y1.ereasep(5*i, 5); y2.ereasep(5*(i-8), f);
y3.ereasep(5*(i-16), f3); }
closegraph();
class Shoot {
public:
void point(int i, int k);
void sh(int i, int k); };
void Shoot::point(int i, int k) {
setcolor(YELLOW); circle(400+i, 400+k, 1); }
void Shoot::sh(int i, int k)
{int j; sound(900);
for(j=0; j<=10; j++)
setcolor(RED);
line(400-j*30+i, 400+k-30*j,400-j*30+i-10, 400+k-30*j-10); delay (30);
setcolor(BLACK);
line(400-j*30+i, 400+k-30*j,400-j*30+i-10, 400+k-30*j-10);
nosound();
char read_key();
char read_key()
{ int y=1;
char x;
_AH=0x01;
geninterrupt(0x16);
y=_FLAGS&0x40;
if(y == 0) {
_AH=0x00;
x=_AL;
return x; }
return '?'; }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

15. Another definition of class Air
Attributes of air-plane:
size, and position.
Another definition of class Air
void main(void) {
int driver = DETECT,mode;
int i,k,f=0,f3=0;
char x;
Air y1, y2, y3;
initgraph(&driver,&mode,"a:\\bgi");
setcolor(WHITE);
line(1,400,400,400);
for ( i = 0; i < 80; i++ )
x=read_key();
if (x =='u') f=f-8;
if (x =='i') f=f+8;
setcolor(BLUE); y1.size=2;
y1.i=5*i; y1.k=f;
y1.planeshow(); /*y1.planeshow(5*i, f); */
delay (300);
y1.ereasep(); }
closegraph();
void Air::ereasep(int i, int k) {
int j;
setcolor(BLACK);
circle(i+5, 200+size+k, size);
circle(i+3, 200+2*size+k, size);
for (j=0; j<=4+3*size; j=j+1)
circle(i+j, 200+k, size);
circle(i+5, 200-size+k, size);
circle(i+3, 200-2*size+k, size); }
char read_key()
{ int y=1;
char x;
_AH=0x01;
geninterrupt(0x16);
y=_FLAGS&0x40;
if(y == 0)
_AH=0x00;
x=_AL;
return x; }
return '?';
#include <graphics.h>
#include<iostream.h>
#include<conio.h>
class Air{
public:
int size; /** the size of the air-plane **/
int i; /** the horizontal position **/
int k /** the vertical position **//
void planeshow();
void ereasep(); };
void Air::planeshow() {
int j;
circle(i+5, 200+size+k, size);
circle(i+3, 200+2*size+k, size);
for (j=0; j<=4+3*size; j=j+size)
circle(i+j, 200+k, size);
circle(i+5, 200-size+k, size);
#include<dos.h>
circle(i+3, 200-2*size+k, size); }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

16. CS3369 Real Time Control Software/Wang Lusheng
Use of return statement
If the type of the function is not void, at least one return statement must be used. The syntax of a return statement is:
return value;
Here value can be a number, variable or math expression.
Examples: return 0; return x; return (x+1-2*y);
Purposes:
1. Terminates the function.
2. Return a value to the parent function.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

17. CS3369 Real Time Control Software/Wang Lusheng
A tricky example of return statement
int f(int i) {
if (i>3)
{ cout<<“good”
return i; }
else
{cout<<“bad”;
return -999; } }
#include<iostream.h>
int f(int i);
void main() {
int x;
x=f(5); }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

18. CS3369 Real Time Control Software/Wang Lusheng
Local Variables
Variables declared within the body of a function are its local variables (we also say the scope of these variables is the body of this function.) (Look at an example)
Variables declared within the body of the main() function of a program is local to the main() function.
A local variable is completely unknown outside its scope. Two local variables of different scopes may have the same name.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

19. CS3369 Real Time Control Software/Wang Lusheng
An Example for Local Variables
#include<iostream.h>
int speed(int i)
int main()
{ int x, y=100;
x=speed(10);
cout<< “The value of y inside main”<<y;
return 0; }
int speed(int i) {
int y;
y=2.1*i-0.15*i*i;
cout<< “The value of y inside speed()”<<y;
cout<<“\n”;
return y; }
Output:
The value of y inside speed() 6
The value of y inside main 100
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

20. CS3369 Real Time Control Software/Wang Lusheng
Variables in parameter list
Variables declared in the parameter list of a function are called formal variables. Their scope is the body of this function.
call-by-value mechanism: by default, when a function is called, the value of the arguments are plugged in the formal parameters. More specifically, if the arguments are variables, their values not the variables themselves are plugged in.
call-by-reference mechanism (will not covered in this course)
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

21. CS3369 Real Time Control Software/Wang Lusheng
An Example for Local Variables
#include<iostream.h>
int speed(int i)
int main()
{ int x, y=100, j=10;
x=speed(j);
cout<< “The value of y inside main”<<y;
return 0; }
int speed(int i) {
int y;
y=2.1*i-0.15*i*i;
cout<< “The value of y inside speed()”<<y;
cout<<“\n”;
return y; }
Output:
The value of y inside speed() 6
The value of y inside main 100
The value of j is passed to speed(), not the variable j.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

22. CS3369 Real Time Control Software/Wang Lusheng
Global Variables
Global variable: universal for the program, declared in the program outside all functions. It can be used and changed everywhere (by any function).
Try to avoid using global variables.
#include<iostream.h>
int g;
void main() {
int x,y;
x=11;
g=80;
y= f(5);
cout<<“The values of g , x and y in main()”
cout<<g<<“ ”<< x<<“ ”<<y; }
int f(int i)
{int x=10;
cout<<“The values of g and x in side f()”;
cout<<g<<“ ” <<x<<“\n”;
g=g+i;
return g; }
OUTPUT:
The values of g and x in side f() 80 10
The values of g , x and y in main()
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

23. CS3369 Real Time Control Software/Wang Lusheng
Another Example for Global Variables
The roots of a quadric equation ax2+bx+c=0 are
x1= (-b+( b2-4ac))/2ac
x2=x1= (-b- ( b2-4ac))/2ac
include<iostream.h>
float x1, x2;
int flag=0;
void roots(float a, float b, float c)
void main(void) {
roots(1.0,2.0, 1.0);
if(flag == 0)
cout<<“The roots are”<<x1<<x2;
else
cout<<“No real root”; }
void roots(float a, float b, float c) {
if (b*b-4*a*c>=0)
x1=(-b+sqrt(b*b-4*a*c))/(2*a*c);
x2 =(-b-sqrt(b*b-4*a*c))/(2*a*c); }
else
flag=1;
x1, x2 and flag are used as global variables. Otherwise, roots must return two values that we do not know how to do it.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

24. CS3369 Real Time Control Software/Wang Lusheng
Global Variables vs Local Variables
If global variables and local variables have the same name, the local variables are valid within their scopes.
#include<iostream.h>
int g=30;
void main() {
int x,y, g; /*g is a local variable */
x=11;
g=80;
y= f(5);
cout<<“The values of g , x and y in main()”
cout<<g<<“ ”<< x<<“ ”<<y; }
int f(int i)
{int x=10;
cout<<“The values of g and x in side f()”;
cout<<g<<“ ” <<x<<“\n”;
/*g is a global variable */
g=g+i;
return g; }
OUTPUT:
The values of g and x in side f() 30 10
The values of g , x and y in main()
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

25. CS3369 Real Time Control Software/Wang Lusheng
while statement
#include<iostream.h>
void main()
{ int a;
cout<<“please enter an integer in [1,9]\n”;
cin>>a;
while (a<1 ||a>9) { }
(Demo the program in the lecture.The question was given in Lab2 as extra exercise since you have not learned while. It can be done using for in a dirty way)
Syntax of while statement:
while (logic_expression) {
statement1;
statement 2; …. }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

26. CS3369 Real Time Control Software/Wang Lusheng
Review and Exercises
variables
for statement
while statement
if statement
switch statement (optional)
functions
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

27. CS3369 Real Time Control Software/Wang Lusheng
Exercises
Question 1: Which of the following words can be used as variable names?
1x11, x11, xx12, _abc, name_variable, for, if, for1, 1while.
Question 2. What are the outputs of the following program?
#include<iostream.h>
void main() {
int i, j;
for (i=1; i<5; i++) {
for(j=1; j<=3; j++)
cout<<i<<j;
cout<“\n”; }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

28. CS3369 Real Time Control Software/Wang Lusheng
Question 3. What are the outputs of the following program?
#include<iostream.h>
void main() {
int i = 10;
if(i<0) cout <<“negative”;
if (i>100) cout<<“too large”;
if (i>=75 && i<=100)
cout<<“excellent”; }
What if the initial value is 88?
Question 4. What are the outputs of the following program?
#include<iostream.h>
void main()
{ int i, j;
for (i=1; i<=5; i++) {
for (j=1; j<=i; j++)
cout<<“ ”; /* There is one space*/
cout <<“**** \n”; }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

29. CS3369 Real Time Control Software/Wang Lusheng
Question 5. What are the outputs of the following program?
#include<iostream.h>
void main() {
int i;
i=1;
while(i<=5)
cout<<i;
i=i+1; }
Question 6. What are the outputs of the following program?
#include<iostream.h>
int max (int x, int y);
void main()
{ int x1=100, x2=102, x3=99;
int temp_max, temp_max1;
temp_max=max(x1,x2);
temp_max1=max(temp_max, x3);
cout<<“The maximum is”;
cout << temp_max1; }
int max (int x, int y)
{ int temp=x;
if (y>temp) temp=y;
return temp;
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CS3369 Real Time Control Software/Wang Lusheng

30. CS3369 Real Time Control Software/Wang Lusheng
Question 7. What are the outputs of the following program?
#include<iostream.h>
int max (int x, int y, int z);
void main()
{ int x1=100, x2=102, x3=99;
int temp_max;
temp_max=max(x1,x2,x3);
cout<<“The maximum is”;
cout << temp_max; }
int max (int x, int y, int z)
{ int temp=x;
if (y>temp) temp=y;
if(z>temp) temp=z;
return temp;
Question 8. What are the outputs of the following program?
#include<iostream.h>
int max (int x, int y, int z);
void main()
{ int temp_max;
temp_max=max(99, 102, 166);
cout<<“The maximum is”;
cout << temp_max; }
int max (int x, int y, int z)
{ int temp=x;
cout<<“The input numbers are”<<x<<y<<z<<“\n”;
if (y>temp) temp=y;
if(z>temp) temp=z;
return temp;
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

31. CS3369 Real Time Control Software/Wang Lusheng
Question 9. What are the outputs of the following program?
#include<iostream.h>
int computation(int x);
void main()
{ int z, w, w1,x=10;
/* x he is a variable that can be used in main() */
z=computation(5);
w=computation(z);
w1=computation(x);
cout<<z<<w<<w1 }
int computation(int x)
/*x here is a formal parameter */
{ int y;
y=x*x+25;
cout<<“input is”<<x<<“\n”;
return y; }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

32. CS3369 Real Time Control Software/Wang Lusheng
Question 10. What are the outputs of the following program?
#include<iostream.h>
int x, int y, int z;
int max ();
void main()
{ int temp_max;
x=90; y=91; z=92;
cout<<z<<“\n”;
temp_max=max();
cout<<“The maximum is”;
cout << temp_max;
cout<<z; }
int max ()
{ int temp=x;
cout<<“The input numbers are”;
cout <<x<<y<<z<<“\n”;
if (y>temp) temp=y;
if(z>temp) temp=z;
z=z+1;
return temp; }
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng

33. CS3369 Real Time Control Software/Wang Lusheng
Question 11. (Moderate) Write a function that takes three integers as its input parameters and outputs the smallest number among the three integers. The prototype of the function is as follows:
int minmum(int x, int y, int z);
Question 12. (Hard) Write a program that (1) asks the user to input an integer from the screen, (2) the input integer should be in the range [0, 100] or [200, 300],
and (3) if the input integer is not in the required ranges, ask the user to re-enter the integer until the integer is in the required ranges.
11/23/2018
CS3369 Real Time Control Software/Wang Lusheng