// lesson 10 e.g.1

#include <iostream.h>

void main()
{
int store[100];
int count;
int i;
int in;

in=1;
count=0;

while((in>=0)&&(count<100))
 {
  cout<<"enter a number, negative when done ";
  cin>>in;
   store[count]=in;

  if(store[count]>=0)  count = count+1;
 }

i=0;
while(i<count)
  {
   cout<<store[i]<<endl;
   i=i+1;
  }

}

//--------------------------------------------------------------------

Notice that in the above program "count" counts the number of legitimate numbers entered (it doesn't 
count the signal negative value).  Since our data in our array starts with position zero to visit every location
in the array we make a variable like i start at 0 and increment it "while less than count".  Look at the second while
loop. This is our model.

Modify this program So that there is a new variable called "max" declared at the start. We are now going to add code at the end of the
existing code:
a) Set max to zero.
b) create a new (third) while loop which is exaclty like the second, including setting i to zero.
c) replace  the cout statement with code that will update max if the current value in store[i] is greater than the current value in max.
d) after the loop, output the maximum value

I'll sign here when I see it working ........................

Modify the program again to find the average of the values entered:
a) At the start of the program create a variable called tot, which should be a double. Create a fourth version of our loop (complete with zeroing of i
and tot. 
b) Each time through the loop add store[i] to tot.
c) after the loop, divide tot by count and output the average value.


Sign...............................


Save your program e.g. as l10ex1.cpp  on the computer while you look at the next 2 programs 

// lesson 10 e.g.2

#include <iostream.h>
void bar(int len)
{
    int i;
    i=0;
    while(i<len)
     {
       cout<<"*";
       i=i+1;
     }
    cout<<endl;
}

void main()
{
int i;
int j;
i=3;
j=25;
bar(20);
bar(i);
bar(j);
bar(i*10);
}

This program demonstrates the use of a function.  Its called 'bar'.  Check out what it does and how it is called by the main function.
Modify the main proram so that it contains a loop which it goes through 10 times and creates bars of length of 1,2,3,4,...10 stars in length.

Sign..............................


//-----------------------

In the program below a new function has been added: "arbar". Arbar takes two parameters, an integer array "data" and and integer "size". Size tells us how many
legitimate numbers the array contains. It then calls "bar" for each legitimate entry in the array. Play a little with the program then I want you to do the following:
a) Cut and paste arbar and bar into the program that you saved from the first part of the lab (above main, below include).
b) At the end of the program call arbar sending it store and count as parameters.

sign.................................




#include <iostream.h>

void bar(int len)
{
    int i;
    i=0;
    while(i<len)
     {
       cout<<"*";
       i=i+1;
     }
    cout<<endl;
}

void arbar(int data[], int size)
{
int c;
while(c<size)
 {
  bar(data[c]);
  c=c+1;
 }
}


void main()
{
int d[5];
d[0]=4;
d[1]=22;
d[2]=14;
d[3]=17;
d[4]=7;
arbar(d,5);

}

/////////////////--------------------------
How non-void functions work:
// Double function (returns number with fractional component).

#include <iostream.h>


double mid(double a, double b)
{
double r;
r=(a+b)/2;
return r;
}

void main()
{
double a;
a=mid(2,9);  
cout<<a<<endl;
}


Cut and paste this program.  Note that because it is a "double" function it "returns" a double value. It must end with something
like "return r" (although this can be anywhere in the function).  When you call "mid" you treat it like a double variable or value and
can use it in assignement statements, logical expressions etc..  Although functions receive any number of parameters that we like, we can 
only "return" one (or zero) values.