1. Engineering Problem Solving with C++, Etter
Chapter 6
Array Function Arguments
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2. Engineering Problem Solving with C++, Second Edition, J. Ingber
Look at New Assignment
P6.12, page 297
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3. Engineering Problem Solving with C++, Second Edition, J. Ingber
One Dimensional Arrays
Array Function Arguments
Sorting with Selection Sort
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4. Engineering Problem Solving with C++, Second Edition, J. Ingber
Function Arguments
ARRAYS
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5. Engineering Problem Solving with C++, Second Edition, J. Ingber
Functions and arrays
An array identifier, without subscripts, references the starting address(first element) of the array.
In C++, arrays are passed by reference. ie the starting address is passed, no size information.
Arrays in C++ to not know their size.
Generally we specify an additional parameter representing the number of elements in the array.
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6. Example of Array Parameter
insert.cpp
A function inserts a number into the array.
Puts it at the end of the list.

7. Engineering Problem Solving with C++, Second Edition, J. Ingber
Example 2, Find Minimum
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8. // This function inputs values into an array until cin.fail() or array
#include <iostream>
using namespace std;
const int MAXSIZE=20;
// This function inputs values into an array until cin.fail() or array
// limit reached
void ReadArr(double a[], int& count) {
double temp;
count = 0;
cin >> temp;
while ( (count < MAXSIZE) && !cin.fail() )
a[count] = temp;
++count; } 8

9. Engineering Problem Solving with C++, Second Edition, J. Ingber
//This function returns the index of the smallest
//value in an array
int FindMin(const double a[], int size) {
int indexOfMin = 0;
for (int i=1; i<size; ++i) {
if (a[i] < a[indexOfMin] ) {
indexOfMin = i;
}//end if
}//end for
return indexOfMin;
}//end FindMin
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10. Engineering Problem Solving with C++, Second Edition, J. Ingber
int main( ) {
double darr[MAXSIZE];
int cnt=0, position=0;
ReadArr(darr, cnt);
position = FindMin(darr, cnt);
cout << "The smallest value in the array is "
<< darr[position] << endl; }
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11. Your Turn cp ~/cs117/outputFunction.cpp
Add a print() function to the program that will be passed an array of ints and its size. It will output the array's elements.

12. Sorting

13. Constant Parameter Promises not to change the array parameter:
int FindMin(const double a[], int size)

14. Going on to Classes
Read Chapter 9, pp

15. Engineering Problem Solving with C++, Second Edition, J. Ingber
Sorting Algorithms
Sorting algorithms arrange the data into either ascending or descending order, based on the values in the array.
Today we'll look at selection sort.
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16. Engineering Problem Solving with C++, Second Edition, J. Ingber
Selection Sort Algorithm
Find minimum value, place it in the first position.
Find next minimum value, place it in the second position.
Continue doing this until you have placed the second to the largest value in the second to the last position.
p.263 of Horstmann
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17. Engineering Problem Solving with C++, Second Edition, J. Ingber
Practice!
Fill in the following table to show how the array is sorted into ascending order using the selection sort.
arr[0] arr[1] arr[2] arr[3] arr[4] 29 45 18 51 36
swap min and arr[0]
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18. Selection Sort Program
selectionSort.cpp

19. Questions
Write a protype for a function that takes an array of ints and its size and returns the sum of the int elements in the array.
The selection sort program sorts a list of 5 numbers. How would you modify the program to sort 10?