import java.util.Date;
import java.util.ArrayList;
import java.util.List;
import java.util.Iterator;
import java.lang.Integer;
public class TestStepTracker {
public static void main(String[] args) {
// We want to have at least 10,000 steps per day to be active
StepTracker tr = new StepTracker(10000);
System.out.println( tr.activeDays() );
System.out.println( tr.averageSteps() );
tr.addDailySteps(9000);
tr.addDailySteps(5000);
System.out.println( tr.activeDays() );
System.out.println( tr.averageSteps() );
tr.addDailySteps(13000);
System.out.println( tr.activeDays() );
System.out.println( tr.averageSteps() );
tr.addDailySteps(23000);
tr.addDailySteps(1111);
System.out.println( tr.activeDays() );
System.out.println( tr.averageSteps() );
}
}
public class StepTracker {
// This is the minimum number of steps needed for a day to be considered active
private int minimumStepsToBeActive = 0;
// This is a list of steps taken each day
private List<Integer> dailySteps = new ArrayList<Integer>();
// This is the constructor called when we create a new StepTracker object
public StepTracker( int minimumSteps ) {
// When we create a new StepTracker object we say how many steps are needed for a day to be active
// we store that value in minimumStepsToBeActive so we can use it later.
this.minimumStepsToBeActive = minimumSteps;
}
// This method is used to add the number of steps taken each day
public void addDailySteps( int steps ) {
// The steps variable is the number of steps taken on a day and we put it in our
// dailySteps list so we can use it later.
this.dailySteps.add( steps );
}
// This method calculated the average number of steps taken
public float averageSteps() {
// Average is total steps for all days divided by the number of days
// start our varilabes at zero
float total = 0;
float count = 0;
// The for loop will run one time for each day
for ( int steps : this.dailySteps ) {
// Add the steps for the day to our total
total += steps;
// Increase our count of days by one
count++;
//System.out.println( count + " days has " + total + " steps");
}
// Calculate the average by dividing total number of steps by total number of days
float average = 0;
if ( count > 0 ) {
average = ( total / count );
}
return average;
}
// This method counts the number of days considered active which means we had
// at least the number of steps specified as our minimumStepsToBeActive.
public int activeDays() {
// Keep a count of active days starting at zero
int activeDayCount = 0;
// The for loop will run one time for each day
for ( int steps : this.dailySteps ) {
// See if the number of steps for that day was at least as high as minimumStepsToBeActive
if (steps >= this.minimumStepsToBeActive) {
// We walked enough for this day to be active so add one to our active day count
activeDayCount++;
}
}
return activeDayCount;
}
} Write, Run & Share Java code online using OneCompiler's Java online compiler for free. It's one of the robust, feature-rich online compilers for Java language, running the Java LTS version 17. Getting started with the OneCompiler's Java editor is easy and fast. The editor shows sample boilerplate code when you choose language as Java and start coding.
OneCompiler's Java online editor supports stdin and users can give inputs to the programs using the STDIN textbox under the I/O tab. Using Scanner class in Java program, you can read the inputs. Following is a sample program that shows reading STDIN ( A string in this case ).
import java.util.Scanner;
class Input {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("Enter your name: ");
String inp = input.next();
System.out.println("Hello, " + inp);
}
}
OneCompiler supports Gradle for dependency management. Users can add dependencies in the build.gradle file and use them in their programs. When you add the dependencies for the first time, the first run might be a little slow as we download the dependencies, but the subsequent runs will be faster. Following sample Gradle configuration shows how to add dependencies
apply plugin:'application'
mainClassName = 'HelloWorld'
run { standardInput = System.in }
sourceSets { main { java { srcDir './' } } }
repositories {
jcenter()
}
dependencies {
// add dependencies here as below
implementation group: 'org.apache.commons', name: 'commons-lang3', version: '3.9'
}
Java is a very popular general-purpose programming language, it is class-based and object-oriented. Java was developed by James Gosling at Sun Microsystems ( later acquired by Oracle) the initial release of Java was in 1995. Java 17 is the latest long-term supported version (LTS). As of today, Java is the world's number one server programming language with a 12 million developer community, 5 million students studying worldwide and it's #1 choice for the cloud development.
short x = 999; // -32768 to 32767
int x = 99999; // -2147483648 to 2147483647
long x = 99999999999L; // -9223372036854775808 to 9223372036854775807
float x = 1.2;
double x = 99.99d;
byte x = 99; // -128 to 127
char x = 'A';
boolean x = true;
When ever you want to perform a set of operations based on a condition If-Else is used.
if(conditional-expression) {
// code
} else {
// code
}
Example:
int i = 10;
if(i % 2 == 0) {
System.out.println("i is even number");
} else {
System.out.println("i is odd number");
}
Switch is an alternative to If-Else-If ladder and to select one among many blocks of code.
switch(<conditional-expression>) {
case value1:
// code
break; // optional
case value2:
// code
break; // optional
...
default:
//code to be executed when all the above cases are not matched;
}
For loop is used to iterate a set of statements based on a condition. Usually for loop is preferred when number of iterations is known in advance.
for(Initialization; Condition; Increment/decrement){
//code
}
While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.
while(<condition>){
// code
}
Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.
do {
// code
} while (<condition>);
Class is the blueprint of an object, which is also referred as user-defined data type with variables and functions. Object is a basic unit in OOP, and is an instance of the class.
class keyword is required to create a class.
class Mobile {
public: // access specifier which specifies that accessibility of class members
string name; // string variable (attribute)
int price; // int variable (attribute)
};
Mobile m1 = new Mobile();
public class Greeting {
static void hello() {
System.out.println("Hello.. Happy learning!");
}
public static void main(String[] args) {
hello();
}
}
Collection is a group of objects which can be represented as a single unit. Collections are introduced to bring a unified common interface to all the objects.
Collection Framework was introduced since JDK 1.2 which is used to represent and manage Collections and it contains:
This framework also defines map interfaces and several classes in addition to Collections.
| Collection | Description |
|---|---|
| Set | Set is a collection of elements which can not contain duplicate values. Set is implemented in HashSets, LinkedHashSets, TreeSet etc |
| List | List is a ordered collection of elements which can have duplicates. Lists are classified into ArrayList, LinkedList, Vectors |
| Queue | FIFO approach, while instantiating Queue interface you can either choose LinkedList or PriorityQueue. |
| Deque | Deque(Double Ended Queue) is used to add or remove elements from both the ends of the Queue(both head and tail) |
| Map | Map contains key-values pairs which don't have any duplicates. Map is implemented in HashMap, TreeMap etc. |