Find Max Using Linear Search

Back to the Program-A-Day homepage

Problem You are given an array of student marks received on a test. Write a method to find the highest mark received on the test and return this mark.		...by students When I learned about arrays, my professor drew out the array as a long rectangle sliced up into multiple slots. This really helped me to visualize what was in each slot of the array at any given time. I found this very helpful to keep track of the contents of the array and I continue to use drawings whenever using arrays.
Solution Create a your method with the proper return type and accepted parameter value (array of ints). public static int findMax(int[] array) { } Use a variable to keep track of the highest value in the array so far. At the beginning of your method, initialize this variable to 0 since we have not started looking through the array yet. int highest = 0; Use a for loop to go through each element in the array to check if it is higher than the current value saved as the highest. for(i = 0; i < array.length; i++) { } For each element in the array, use an if statement to determine whether it is larger than the current highest variable. In order to determine this, use the '>' operator. If the current element is greater than the highest variable, you can set the highest variable to the current element in the array. if(array[i] > highest) { highest = array[i]; } After the for loop, return your highest variable. return highest; Putting everything together, here's what your entire method should look like: public static int findMax(int[] array) { int i; // loop iterator int highest = 0; for(i = 0; i < array.length; i++) { if(array[i] > highest) { highest = array[i]; } } return highest; }
Code Solution Code /* This program creates and prints out a random array of 20 marks (between 0 and 100). It uses the findMax method to find the maximum mark and then prints out this mark. */ public class LinearSearchForMax { public static void main(String args[]) { int i, x; int highestMark; int[] marks = new int[20]; // Create an array of random marks for(i = 0; i < marks.length; i++) { marks[i] = (int)(Math.random() * 100); // generates a random number from 0-100 System.out.println("marks["+i+"] = " + marks[i]); } // Call your method to find the maximum mark highestMark = findMax(marks); // Display the results of your search. System.out.println("The highest mark is: " + highestMark); } public static int findMax(int[] array) { int i; // loop iterator int highest = 0; for(i = 0; i < array.length; i++) { if(array[i] > highest) { highest = array[i]; } } return highest; } }

Back to the Program-A-Day homepage