Q #1: Write a Java program to find the smallest number in an array?
Input : int [] num ={9, 3, 4, 2 ,7}
Output: 2
A: class SmallestNumberInAnArray {
public static void main(String[] args) {
int [] num = {9,3,4,2,7};
int len = num.length;
int tem = num[0];
for(int i=0; i < len; i++){
if(num[i] < tem){
tem=num[i];
}
}
System.out.println("Smallest number in an array - "+tem);
}
}
Q #2: Sort the Integer array without using any Java inbuild functions?
Input : int [] num ={9, 3, 4, 2 ,7}
Output: 2,3,4,7,9
A: class SortInteger {
public static void main(String[] args) {
int[] num = {9,3,4,2,7};
int len = num.length;
int temp = 0;
for (int i = 0; i < len-1; i++) {
for (int j = i + 1; j < len; j++) {
if (num[i] > num[j]) {
temp = num[i];
num[i] = num[j];
num[j] = temp;
}
}
}
for (int n: num)
System.out.print(n + " ");
}
}
Q #3: Write a java program to reverse the string?
Input : My name is abc
Output: yM eman si cba
A #1: class ReverseString {
public static void main(String[] args) {
String value ="My name is abc";
String [] split = value.split(" ");
for(int i=0;i<split.length;i++){
StringBuilder sb = new StringBuilder(split[i]);
sb.reverse().append(" ");
System.out.print(sb);
}
}
}
A #2: class ReverseString {
public static void main(String[] args) {
String value ="My name is abc";
String [] split = value.split(" ");
for(int i=0;i<split.length;i++){
char [] ch = split[i].toCharArray();
int len = ch.length;
for(int j=len-1;j>=0;j--){
System.out.print(ch[j]);
}
System.out.print(" ");
}
}
}
Q #4: Write a java program to count 1 and 0 in a given string?
Input : String str = "101010";
Output: ones - 3, zeros - 3
A : class CountNumberOfOnesZeros {
private static int ones;
private static int zeros;
public static void main(String[] args) {
String value="101010";
char [] ch = value.toCharArray();
for(int i=0;i<ch.length;i++){
int num = Integer.parseInt(String.valueOf(ch[i]));
if(num == 0) {
zeros++;
}else{
ones++;
}
}
System.out.println("zeros "+zeros);
System.out.println("ones "+ones);
}
}
Q #5: Write a java program for an array of integers, find two index such that they add up to a specific
target number?
Input #1: nums = [2,7,11,15], target = 9
Output #1: [0,1]
Input #2: nums = [3,2,4], target = 6
Output #2: [1,2]
A : class ArrayOfTwoIndex{
public static int[] indexOf(int [] nums, int target){
int len = nums.length;
for(int i=0;i<len;i++){
for(int j=i+1;j<len;j++){
if(nums[i]+nums[j]==target){
return new int[]{i,j};
}
}
}
return new int[]{-1,-1};
}
public static void main(String[] args) {
int [] nums = {2,7,11,15};
int target =22;
for(int i : indexOf(nums,target))
System.out.print(i+" ");
}
}
Q #6: Write a java program to remove duplicate numbers from the sorted array?
Input : int [] nums ={1,2,2,2,3,5};
Output: [1,2,5]
A : import java.util.*;
import java.util.stream.Collectors;
class RemoveDuplicateNumbers {
public static void main(String[] args) {
int [] nums ={1,2,2,2,3,5};
Set sets = Arrays.stream(nums).boxed().collect(Collectors.toSet());
for(String i : sets)
System.out.print(i);
}
}
Q #7: Write a java program to remove duplicate numbers from the sorted array using inbuild funstions?
Input : int [] nums ={1,2,2,2,3,5};
Output: [1,2,5]
A : import java.util.*;
import java.util.stream.Collectors;
class RemoveDuplicateNumbers {
public static void main(String[] args) {
int [] nums ={1,2,2,2,3,5};
Set sets = Arrays.stream(nums).boxed().collect(Collectors.toSet());
for(String i : sets)
System.out.print(i);
}
}
Q #8: Write a java program to remove duplicate numbers from the sorted array
without
using inbuild
funstions?
Input : int [] nums ={1,2,2,2,3,5};
Output: [1,2,5]
A : class RemoveDuplicateNumbers {
public static void main(String [] args){
int[] nums = {1, 2, 2, 3, 4, 5};
int[] temp = new int[nums.length];
int j = 1, k = 0;
int target = 0, count = 0;
for (int i = 0; i<nums.length; i++) {
if (j == nums.length) {
temp[k++] = nums[i];
} else {
target = nums[j++];
}
if (nums[i]<target) {
temp[k++] = nums[i];
} else if (nums[i] == target) {
count++;
}
}
for (int i = 0; i<=temp.length - count; i++) {
System.out.print(temp[i]);
}
}
}
Q #9: Write a java program to reverse the string?
Input : String value = "apple";
Output: elppa
A : class ReverseTheString{
public static void main(String[] args) {
String value ="apple";
for(int i=value.length()-1;i>=0;i--){
System.out.print(value.charAt(i));
}
}
}
Q #10: Write a java program to move all the zeros to end of the array?
Input : int [] num = {0,1,0,3,12};
Output: 1,3,12,0,0
A : import java.util.*;
import java.util.stream.Collectors;
class MoveAllZerosToEndOfArray {
public static void main(String[] args) {
int [] num = {0,1,0,3,12};
int [] result = new int[num.length];
int j=0;
for(int i=0;i<num.length;i++){
if(num[i]>0){
result[j++]=num[i];
}
}
List integerList = Arrays.stream(result).boxed().collect(Collectors.toList());
System.out.println(integerList);
}
}
Q #11: Write a java program whether string is palindrome?
Input : String value = "madam";
Output: String is palindrome
A : class StringPalindrom {
public static void main(String[] args) {
String value = "madam";
int length=value.length();
boolean isPalindrome=true;
for(int i=0;i<length;i++){
if(value.charAt(i)!=value.charAt(length-1-i)){
isPalindrome=false;
}
}
String result = isPalindrome? value+" string is palindrome" : value+" string is not palidrome";
System.out.println(result);
}
}
Q #12: Write a java program whether number is palindrome?
Input : int value = "151";
Output: Integer is palindrome
A : class IntegerPalindrom {
public static void main(String[] args) {
int num = 151;
int actualValue=0;
int expctedValue=num;
while (num>0){
actualValue=(actualValue*10)+num%10;
num=num/10;
}
String result = actualValue==expctedValue? "Its paliandrome" : "Its not a paliandrome";
System.out.print(result);
}
}
Q #13: Write a java program where,
Input : String str = "AABBCABCGG";
Output: A:2 B:2 C:1 A:1 B:1 C:1 G:2
A : class CountDuplicateCharInString {
public static void main(String[] args) {
String str = "AABBCABCGG";
char [] ch = str.toCharArray();
int j=1;
int count=1;
for(int i=0;i<ch.length;i++){
if(ch[j]==ch[i]){
count++;
System.out.println(ch[i]+":"+count);
count--;
j+=2;
i+=1;
}else{
System.out.println(ch[i]+":"+count);
System.out.println(ch[j]+":"+count);
j+=2;
i+=1;
}
}
}
}
Q #14: Write a java program to remove the duplicate from String?
Input : String str = "apple";
Output: aple
A : class RemoveDuplicateString {
public static void main(String[] args) {
String value = "apple";
char[] ch = value.toCharArray();
char[] temp = new char [ch.length];
int j=1,k=0,count=0;
for(int i=0;i<ch.length;i++){
if(i==ch.length-1){
temp[k++]=ch[i];
}else if(ch[i]==ch[j++]){
count++;
}else{
temp[k++]=ch[i];
}
}
for(int i=0;i<ch.length-count;i++){
System.out.print(temp[i]);
}
}
}
Q #14: Write a java program to print the second largest number in an array list(not a sorted array)?
Input : int [] num = {3,2,5,1,6};
Output: 2
A : class SecondLargestArray {
public static void main(String[] args) {
int temp = 0;
for (int i = 0; i < num.length; i++) {
for (int j = i + 1; j < num.length; j++) {
if (num[i] > num[j]) {
temp = num[i];
num[i] = num[j];
num[j] = temp;
}
}
}
System.out.println(num[1]);
}
}
Q #15: Write a java program to reverse the integer?
Input : int num = 456;
Output: 654
A : class ReverseInteger {
public static void main(String[] args) {
int num = 456;
int temp=0;
while(num>0){
temp=(temp*10)+num%10;
num=num/10;
}
System.out.println(temp);
}
}
Q #16: Write a java program to find number of words in a string?
Input : String str = "This this is is done by Saket Saket is Saket";
Output: this-2, is-3, done-1, by-1, Saket-3
A : class NumberOfWordsInString {
public static void main(String[] args) {
String str = "This this is is done by Saket Saket is Saket";
String[] split = str.split(" ");
LinkedHashMap hashMap = new LinkedHashMap<>();
for (int i = 0; i < split.length; i++) {
if (hashMap.containsKey(split[i])) {
int count = hashMap.get(split[i]);
hashMap.put(split[i], ++count);
} else {
hashMap.put(split[i], 1);
}
}
System.out.println(hashMap);
}
}
Q #17: Write a java program to find the missing sequence number?
Input : 1,2,3,4,6,7,8
Output: 5
A : class MissingSequenceNumber {
public static void main(String[] args) {
int [] num ={1,2,3,4,6,7,8};
int j=1;
for(int i=0;i<num.length-1;i++){
if(num[j++]-num[i]!=1){
System.out.println(j);
}
}
}
}
Q #18: Write a java program to find You are given a string s and an integer array indices of the same length.
The string s will be shuffled such that the character at the ith position moves to indices[i] in the shuffled
string?
Example :1
Input : s= "codeleet", indices=[4,5,6,7,0,2,1,3]
Output: leetcode
Example :2
Input : s= "abc", indices=[0,1,2]
Output: abc
A : class ShufflingString {
public static shuffleString(String s, int [] indices){
Map<Integer, Character> map = new LinkedHashMap<>();
for(int i=0;i<indices.length;i++){
map.put(i,s.chartAt(i));
}
StringBuilder sb = new StringBuilder();
for(int i=0;i<indices.length;i++){
sb.append(map.get(i));
}
return sb.toString();
}
public static void main(String[] args) {
String s = "codeleet";
int [] num ={4,5,6,7,0,2,1,3};
shuffleString(s,num);
}
}
Q: What is the highest mountain in the world?
A: Mount Everest is the highest mountain in the world.