##
**Problem:**

Given a 2 sorted array find mean, median & mode

##
**Solution:**

1) Two Sorted arrays can be merged in O(n) time.

2) Calculating mean is simple i.e.

a) calculate k = summission of mergedarray[i]

b) do k/mergearray.length

c) display k as mean value

3) Calculating Median

a) In case total no of element is ODD, int m = mergedarray.length/2, then display m as median value

b) In case total no of element is EVEN, int m = mergedarray.length/2,

int val = (mergedarray[m]+mergedarray[--m])/2

display val as median

4) Calculating Mode is simple i.e.

-- find number which occurs max number of times.

## Code:

import java.util.ArrayList; public class MyDS { int[] no,count; int ptr = 0; public MyDS(int n) { no = new int[n]; count = new int[n]; } public void add(int val, int occ) { no[ptr] = val; count[ptr] = occ; ptr++; } public ArrayListGOOD LUCK! Merry Christmas & Happy New Year !!getModeValue() { int max = 0,z=0; ArrayList k = new ArrayList (); for (int i = 0; i < count.length; i++) { if( count[i] > max) { max = count[i]; z = i; } } k.add(no[z] + " " + max); for (int i = 0; i < count.length; i++) { if( count[i] == max && z != i ) { if(!k.contains(no[i] + " " + max)) k.add(no[i] + " " + max); } } return k; } } import java.util.ArrayList; public class Merge2SortedArray { int arr1[],arr2[],farr[]; int ptr1,ptr2,fptr; void init(int[] a, int[] b ) { arr1 = a; arr2 = b; farr = new int[arr1.length+arr2.length]; merge(); } private void merge() { // TODO Auto-generated method stub /** * while-loop to tackle merging of sorted arrays of unequal length * for-loop is ok for merging equal length sorted array. * */ while (ptr1 <= arr1.length || ptr2 <= arr2.length) { if(arr1[ptr1] < arr2[ptr2]) { farr[fptr] = arr1[ptr1]; fptr++; ptr1++; }else if( arr2[ptr2] < arr1[ptr1] ) { farr[fptr] = arr2[ptr2]; fptr++; ptr2++; }else { farr[fptr] = arr1[ptr1]; fptr++; farr[fptr] = arr1[ptr1]; fptr++; ptr1++; ptr2++; } if(ptr1 >= arr1.length) { copyArr2(); break; }else if( ptr2 >= arr2.length) { copyArr1(); break; } } median(); mean(); MyDS ds = new MyDS(farr.length); for (int i = 0; i < c; i++) { int occurence = mode(farr[i]); ds.add(farr[i],occurence); } displayMode(ds); } private void displayMode(MyDS ds) { // TODO Auto-generated method stub ArrayList modeValue = ds.getModeValue(); System.out.println("And the mode value is "); for (String string : modeValue) { System.out.println(string); } } private int mode(int k) { // TODO Auto-generated method stub int z = 0; for (int i = 0; i < c; i++) { if(farr[i] == k) z++; } return z; } private void mean() { // TODO Auto-generated method stub int sum =0; for (int i = 0; i < c; i++) { sum += farr[i]; } System.out.println("And mean is " + sum/c); } int c = 0; private void median() { // TODO Auto-generated method stub for (int k : farr) { if(k != 0) { System.out.print(k + " "); c++; } } System.out.println("\n" + "And the median is "); if((c%2)==0) { int med = c/2; avgingMideans(med,--med); } else System.out.println(farr[((c+1)/2)-1]); } private void avgingMideans(int c2, int c3) { // TODO Auto-generated method stub int k = (farr[c2]+farr[c3])/2; System.out.println(k); } private void copyArr1() { // TODO Auto-generated method stub for (int i = ptr1; i < arr1.length; i++) { farr[fptr] = arr1[i]; fptr++; } } private void copyArr2() { // TODO Auto-generated method stub for (int i = ptr2; i < arr2.length; i++) { farr[fptr] = arr2[i]; fptr++; } } public static void main(String[] args) { // TODO Auto-generated method stub int[] a = {6,6}; int[] b = {2,4}; new Merge2SortedArray().init(a ,b); } }