Learn Quality Testing

import java.util.HashMap ; import java.util.Map ; public class OccurenceOfCharInString { public static void main ( String [] args) { System . out .println( getCharacterCount ( "malayalam" )); } static Map < Character , Integer > getCharacterCount ( String str){ HashMap < Character , Integer > charMap = new HashMap<>(); char [] strArr =str.toCharArray(); for ( char c : strArr ) { if ( charMap .containsKey( c )) charMap .put( c , charMap .get( c )+ 1 ); else charMap .put( c , 1 ); } return charMap ; } }

  import java.util.Arrays ; public class AddTwo { public static void main ( String [] args) { int [] ar ={ 7 , 7 , 4 , 3 , 8 }; System . out .println( Arrays . toString ( new AddTwo().sum( ar , 10 ))); } public int [] sum ( int [] arr, int num){ int [] sumnum = new int [ 2 ]; for ( int i= 0 ;i<arr. length ;i++){ for ( int j=i+ 1 ;j<arr. length ;j++){ System . out .println( "i=" +i+ " j=" +j); if (arr[i]+arr[j]==num) { sumnum [ 0 ]=arr[i]; sumnum [ 1 ]=arr[j]; } } } return sumnum ; } }

  import java.util.Stack ; public class ReverseStack { public static void main ( String [] args) { String str = "reverse" ; String rev= "" ; Stack < Character > stack = new Stack<>(); for ( int i= 0 ;i< str .length();i++) stack .push( str .charAt(i)); while (! stack .isEmpty()) rev=rev+ stack .pop(); System . out .println(rev); } }

  public class Fibonnaci { public static void main ( String [] args) { int ser = 5 ; int one= 0 ; int two= 1 ; for ( int i= 0 ;i< ser ;i++){ System . out .println(one+ "" ); int sum =one+two; one=two; two= sum ; } } }

  import java.util.Stack ; public class BalancedString { public static void main ( String [] args) { String check = "({}{}([{}]))" ; System . out .println( isBalanced ( check )); } public static boolean isBalanced ( String str){ char [] arr =str.toCharArray(); Stack < Character > st = new Stack<>(); for ( Character ch : arr ) { if ( ch == '[' || ch == '{' || ch == '(' ) st .push( ch ); else { char last = st .pop(); if ( last == '{' && ch != '}' ) return false ; else if ( last == '(' && ch != ')' ) return false ; else if ( last == '[' && ch != ']' ) return false ; } } return st .size()== 0 ; } }

  public class InsertionSort { void sort ( int arr[]) { int n = arr. length ; for ( int i = 1 ; i < n ; ++i) { int key = arr[i]; int j = i - 1 ; /* Move elements of arr[0..i-1], that are greater than key, to one position ahead of their current position */ while (j >= 0 && arr[j] > key ) { arr[j + 1 ] = arr[j]; j = j - 1 ; } arr[j + 1 ] = key ; } } /* A utility function to print array of size n*/ static void printArray ( int arr[]) { int n = arr. length ; for ( int i = 0 ; i < n ; ++i) System . out .print(arr[i] + " " ); System . out .println(); } // Driver method public static void main ( String args[]) { int arr [] = { 12 , 11 , 13 , 5 , 6 }; InsertionSort ob = new InsertionSort(); ob .sort( arr ); ...