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### 2018-09-26 More Arrays

posted Sep 26, 2018, 5:44 AM by Konstantinovich Samuel   [ updated Sep 27, 2018, 7:03 AM ]
 Homework - Complete the lab (due Friday)Exam Modification (Due to Fire Drill)Split into 2 parts:   Coding Questions Friday  Multiple Choice Question Monday.-Go over problems where there was difficulty public static void main (String[]args){``` char[] fakeString = {'m','c','g','k','s'}; for (int i = 0; i < fakeString.length; i++){ System.out.println(fakeString[i] + " "); } // Three different ways to initialize an int[][]. //Applies to 2D arrays of another type too. int[][] multiA = new int[3][4]; // first number is the # of arrays in multiA // second number is the # of items of each array in multiA // for multiA, all arrays must be the same length. // for multiB, the arrays within can have different lengths. int[][] multiB = new int[3][];`````` multiB[0] = new int[4]; // each row, 0,1 and 2 mutliB[1] = new int[4]; // can be a different length multiB[2] = new int[4]; int[][] multiC = new int[][]{ {0,0,0,0}, // can make these different lengths as well {0,0,0,0}, {0,0,0,0}, }; // for multiC, arrays within can have different lengths. }````Lab + HW (due Friday in case you can't finish)``For all problems:``Write test cases. When given an assignment:Never change the classname, parameters, return type, or the names of the methods assigned.Make a new repos MKS21X-arraysinclude the file ArrayDemo.java which has several static methods:Do not use built in array methods in Arrays (do it yourself!) 0a. Make a function to print a 1D array of ints.`public static void printArray(int[]ary){}`0b. Make a function to print a 2d array of ints.`public static void printArray(int[][]ary){}`Notice both 0a and 0b share the same name. This is called method overloading.Overloading is allowed when the parameters differ in type and/or quantity.1. Calculate and return how many zeros are in the parameter(a rectangular 2D array of integers)`public static int countZeros2D(int[][] nums){``}`2a. Modify a given 2D array of integer as follows:Replace all the of values with 1's EXCEPT when the row number is the same as the column number:you must fill those with 3's instead.`public static void fill2D(int[][] vals){``}`2b. Make a new 2d array the same dimensions as the given parameter. Fill that array with with 1's, except where the value of the original array is negative:you must fill those with 3's instead.//You may NOT modify the parameter vals.```public static int[][] fill2DCopy(int[][] vals){``}``