Idiot Programmer

Program to find the frequency of characters in given string in java  For Explanation Watch Video : Code:: import java.util.*; import java.io.*; import java.lang.*; class Test{ public static void main(String[] args) { String name = "idiot"; Map<Character,Integer> map = new HashMap<Character,Integer>(); for(int i=0;i<name.length();i++){ Character ch = name.charAt(i); map.put(ch,map.getOrDefault(ch,0)+1); } System.out.println(map); for(Map.Entry<Character,Integer> e : map.entrySet()){ System.out.println(e.getKey()+" "+e.getValue()); } } } o/p: {d=1, t=1, i=2, o=1} d 1 t 1 i 2 o 1

 remove duplicate words from string in java For Explanation Watch Video:  Program:: import java.util.*; class College { public static void main(String[] args){ String sen = " Sam went went to to to his business "; String[] arr = sen.split(" "); //arr={Sam,went,went,to,to ,to ,his ,business}; Set<String> s = new LinkedHashSet<String>(); for(int i=0;i<arr.length;i++){ s.add(arr[i]); } for(String ss:s){ System.out.print(ss+" "); } System.out.println(); } } o/p:  Sam went to his business Using Java 8 import java.util.*; class College { public static void main(String[] args){ String sen = "Sam went went to to to his business"; sen = Arrays.stream(sen.split(" ")).distinct().collect(Collectors.joining(" "); } }

 Reverse a string using Stack in java Explanation Of code: Code: import java.util.Stack; class Test{ public static void main(String[] args){ String s = "Baburao"; System.out.println(reverse(s));     } public static String reverse(String s){ Stack<Character> st = new Stack<>(); String reverse = ""; for(int i=0;i<s.length();i++){ st.push(s.charAt(i)); } while(st.size()!=0){ reverse = reverse + st.pop(); } return reverse; } } o/p:oarubaB