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Write a program that reads an unspecified number of scores and determines how many scores
are above or equal to the average and how many scores are below the average. Enter a
negative number to signify the end of the input. Assume that the maximum number of scores
is 100.
Exercise 16 - 02: Averaging an array
Write two overloaded methods that return the average of an array with the following headers:
public static int average(int[] array);
public static double average(double[] array);
Exercise 16 - 03: Finding the index of the smallest element
Write a method that returns the index of the smallest element in an array of integers. If there
is more than one such element, return the smallest index. Use {1, 2, 4, 5, 10, 100, 2, –22} to
test the method.
Exercise 16 - 04: Reversing an array
Write a method to reverse an array without creating new arrays. Use {1, 2, 3, 4, 5, 6} to test
the method.
Exercise 16 - 05: Computing average
Write a method that returns the average of an unspecified number of numeric arguments.
Exercise 16 - 06: Timing execution
Write a program that randomly generates an array of 100000 integers and a key. Estimate the
execution time of invoking the linearSearch method. Sort the array and estimate the execution
time of invoking the binarySearch method. You can use the following code template to obtain
the execution time:
long startTime = System.currentTimeMillis();
perform the task;
long endTime = System.currentTimeMillis();
long executionTime = endTime - startTime;
public class LinearSearch {
/** The method for finding a key in the list */
public static int linearSearch(int[] list, int key) {
for (int i = 0; i < list.length; i++)
Chapter 16: Arrays - Exercises
Exercise 16 - 01: Analyzing scores
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if (key == list[i])
return i;
return -1;
}
}
public class BinarySearch {
/** Use binary search to find the key in the list */
public static int binarySearch(int[] list, int key) {
int low = 0;
int high = list.length - 1;
while (high >= low) {
int mid = (low + high) / 2;
if (key < list[mid])
high = mid - 1;
else if (key == list[mid])
return mid;
else
low = mid + 1;
}
return -low - 1;
}
}
Exercise 16 - 07: Summing all the numbers in a matrix
Write a method that sums all the integers in a matrix of integers. Use {{1, 2, 4, 5}, {6, 7, 8,
9}, {10, 11, 12, 13}, {14, 15, 16, 17}} to test the method.
Exercise 16 - 08: Adding two matrices
Write a method to add two matrices. The header of the method is as follows:
public static int[][] addMatrix(int[][] a, int[][] b)
To test randomly generates two integer arrays.
In order to be added, the two matrices must have the same dimensions and the same or
compatible types of elements. As shown below, two matrices are added by adding the two
elements of the arrays with the same index:
