FAQ In Interview

Friends I have set of programs that commonly asked in interviews. I hope it will very useful to freshers. (pgm in java)

1)  Return a new array with only positive numbers from the given array. The elements in the resulting array shall be sorted in the ascending order.

public static int[] retainPositiveNumbers(int[] a) {

        List array=new ArrayList();

     for(int i : a)

     {

     if(i>=0)

     array.add(i);

     }

     Object t[];

     t=array.toArray();

     Arrays.sort(t);  

     int idx = 0;

     int[] arrayInt = new int[array.size()];

     for(Integer v : array)

       arrayInt[idx++] = v;    

     return arrayInt;

    }

2)  Reverse each word in the original String while maintaining the word order. 

       For example:   parameter: "Hello world",   result: "olleH dlrow"

    public static String reverseWords(String s) {

        String arr[]=s.split(" ");

     StringBuffer buf=new StringBuffer();

     for(int j=0;j

     for(int i=arr[j].length()-1;i>=0;i--){

     buf.append(arr[j].charAt(i));

     }

     buf.append(" ");

     }

     s=buf.toString();

     return s;        

    }

3)  Implement Palindrome function.

public static boolean isPalindrome(String s) {

       int low = 0;

       int high = s.length() - 1;

       while(low <>

         if(s.charAt(low) != s.charAt(high))

                return false; 

        low++;

        high--;

    }

   return true;

 }

4)   Return a new array where the order of elements has been reversed from the original  array. 

public static Object[] reverseArray(Object[] a) {

         Object t[];

     t=new Object[a.length];

      for(int i=a.length-1,j=0;i>=0;i--,j++)

       t[j]=a[i];

         return t;  

    }