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C++ LESSON 7: ✍🏻✍🏻......🌿🌿🌿......✍🏻✍🏻                 Loop ➾are used to repeat a block of code ➾There are three types of loops:        🌿🌿⓵.For Loop 🌿🌿 ➾is used to iterate a part of the program several times ➾The syntax for a for loop is : for(initialization; condition; incr/decr){ //code to be executed } ➾It executes initial statement once, the test takes place before each iteration, then executes statement and iteration expression repeatedly, until the value of condition becomes false.       🌿🌿⓶. while loop🌿🌿 ➾ is used to iterate a part of the program several times ➾ If the number of iteration is not fixed, it is recommended to use while loop than for loop ➾ The syntax of while loops is given by  : while(condition){ //code to be executed } 🌿🌿⓷.Do - While loop 🌿🌿 ➾ is used to iterate a part of the program several times. ➾If the number of iteration is not fixed and you must have to execute the loop at least once, it is recommended to use do-while loop.  ➾do-while loop is executed at least once because condition is checked after loop body . ➾The syntax of do-while loops is given by  : do{ //code to be executed } while(condition); Share our channel 👇👇 https://t.me/Africacoder

👉👉🌿🌿Answer🌿🌿👈👈 ⓵. #include<iostream> using namespace std; int main () { cout<<”Enter a real number: ”; float num; cin >> num; if (num > 5) { cout << num << ”is greater than 5”; } return 0; }  ⓶. #include<iostream> using namespace std; int main(){ float num1, num2, num3; cout << ”Enter three numbers: ”; cin >> num1 >> num2 >> num3; if(num1 >= num2 && num1 >= num3) { cout << ”Largest number: ” << num1; } if (num2 >= num1 && num2 >=num3) { cout << ”Largest number: ” << num2; } if (num3 >= num1 && num3 >= num2) { cout << ”Largest number: ” << num3; } return 0; } ⓷. #include<iostream> using namespace std;  int main () { cout<<”Enter a number: ”; int num; cin >> num; if (num % 2 == 0) { cout << num << ”is even number”; } else { cout<< num <<” is odd number”<<endl; } return 0; } ⓸. #include <iostream> using namespace std; int main () { int num; cout<<”Enter a number to check grade:”; cin>>num; if (num < 0 || num > 100) { cout<<”wrong number”; } else if(num >= 0 && num < 50) { cout<< ”Fail”; } else if (num >= 50 && num < 60){ cout<< ”accepted”; } else if (num >= 60 && num < 70){ cout<< ”middle”; } else if (num >= 70 && num < 80) { cout<< ”good”; } else if (num >= 80 && num < 90) { cout<< ”very good”; } else (num >= 90 && num <= 100){cout<< ”excellent”; } return 0; }

----------🧑‍💻🧑‍💻🧑‍💻🧑‍💻🧑‍💻JAVA-----------🧑‍💻🧑‍💻🧑‍💻🧑‍💻 LESSON 10: Creating objects in java ✳️An object is a basic unit of Object-Oriented Programming and represents the real life entities. It consists of:- ⚜️State means the attributes. ⚜️Behavior means the methods of an object. ⚜️Identity means the unique name to an object. the four ways of creating objects in java 1. using new key word //Test t = new Test(); 2. Using Class.forName( String className) method; Test obj = (Test)Class.forName("com.p1.Test").newInstance(); 3. using clone() method /Test t = new Test(); Test t2 = (Test)t1.clone(); 4. Deserialization it is is technique of reading an object from the saved state in a file. ✅example using the first way: class Animal {} class Dog extends Animal {} class Cat extends Animal {} public class Test { // using Dog object Animal obj = new Dog(); // using Cat object obj = new Cat(); } SUPPORT US BY JOINING AND SHARING; https://t.me/Africacoder 😊

-----🧑‍💻🧑‍💻🧑‍💻🧑‍💻🧑‍💻🧑‍💻JAVA---🧑‍💻🧑‍💻🧑‍💻🧑‍💻👉 LESSON 9: CONSTRUCTORS in Java ✳️ A constructor in Java is a special method that is used to initialize objects. The constructor is called when an object of a class is created. It can be used to set initial values for object attributes. How Constructors are Different From Methods in Java?    ❤️ Constructors must have the same name as the class within which it is defined while it is not necessary for the method in Java.     ❤️Constructors do not return any type while method(s) have the return type or void if does not return any value.     ❤️Constructors are called only once at the time of Object creation while method(s) can be called any number of times. Example: look the sample code having two constructors; package ubJapro1; //import java.util.*; public class Firsta {   public static void main(String[] args) {       Firsta2 firs  = new Firsta2("ashe",34,76.4);// constructor 1   Firsta2 firs2  = new Firsta2("asegid",32,70.4);// constructor 2      System.out.println(firs.name+" is your name.");       firs2.home();      }                       }

🙋🙋🙋🙋🙋🙋🙋🙋🙋🙋 exercise on conditional statement 🙋🙋🙋🙋🙋🙋🙋🙋🙋🙋 Write a c++ program to ⓵.Check if a real number x is greater than 5 using if statement ⓶. find the largest number among three numbers using if statement.  ⓷.Check whether a number is even or odd  using if else ⓸.Check whether a student’s grade is fail, accepted, middle, good, very good, or excellent using nested if ❗❗don't forget to answer ❗❗

C++ LESSON 6: ✍🏻✍🏻......🌿🌿🌿......✍🏻✍🏻     Conditional statement ➾if statement is a logical expression and it is used to test a certain condition ➾There are various types of if statements in C++ as follows:     ⓵. if statement ➬ It is executed if condition is true otherwise the next step after the condition shall be executed.     ⓶. if-else statement syntax : if(condition) { //code if condition is true } else { //code if condition is false }    ⓷. nested if statement Syntax : if(condition 1) { //code to be executed if condition1 is true } else if(condition 2) { //code to be executed if condition2 is true } else if(condition 3) { //code to be executed if condition3 is true } ... else{ //code to be executed if all the conditions are false } Share our channel 👇👇 https://t.me/Africacoder

C++ LESSON 5: ✍🏻✍🏻......🌿🌿🌿......✍🏻✍🏻 Standard input and output             stream (iostream) ⓵. Standard Input Stream (cin)  ➾is an instance of istream class. ➾is said to be attached to the standard input device ➾is used together with the extraction operator >> as shown in the following examples For examples: #include <iostream> using namespace std; int main() { int age; cout <<“Please enter your age: ”; cin >> age; cout << “I am ” << age << “ years old.”<<endl; return 0; } ⓶.Standard Output Stream                       (cout) ➾ is an instance of ostream class ➾is used in conjunction with the stream insertion operator  (<<) ➾Multiple insertion operations (<<) may be chained in a single statement:  int x=2; cout<<“y ” <<“=” << x; ➾To insert a line break, a new-line character shall be inserted at the exact position in order to break the line. In C++, a new-line character can be specified as \n 🙋🙋🙋Question:🙋🙋🙋 ❓Write a code for entering someone’s first, middle and last names then print the full name. ❗❗  Don't forget to Comment your answer❗❗ share our channel https://t.me/Africacoder

---------------Java🧑‍💻🧑‍💻🧑‍💻------------------- LESSON 8: WRAPPER CLASSES IN JAVA ✅Wrapper classes provide a way to use primitive data types (int, boolean, etc..) as objects. ✳️Sometimes you must use wrapper classes, for example when working with Collection objects, such as ArrayList, where primitive types cannot be used (the list can only store objects): example: ArrayList<Integer> myNumbers = new ArrayList<Integer>(); // Valid Creating Wrapper Objects To create a wrapper object, use the wrapper class instead of the primitive type. To get the value, you can just print the object: Example public class Main { public static void main(String[] args) { Integer myInt = 5; Double myDouble = 5.99; Character myChar = 'A'; System.out.println(myInt); System.out.println(myDouble); System.out.println(myChar); } } https://t.me/Africacoder share our channel 😊

---------------------JAVA🧑‍💻🧑‍💻🧑‍💻🧑‍💻🧑‍💻----------- LESSON 7:                    LOOPS AND NESTED LOOPS ✳️Looping in java helps by facilitating the execution of of a set of instructions repeatedly while some condition evaluates to true.   1. While-loops: allows the code to be executed repeatedly based on a given Boolean condition.    while (boolean condition)      {    loop statements...    }   2. for-loops: unlike while statement, it consumes the initialization, condition, and increment/decrement. for (initialization condition; testing condition;increment/decrement) {     statement(s) }   3. do-while:  do while loop is similar to while loop with only difference that it checks for condition after executing the statements.   do {     statements.. } while (condition); sample example for for-loop: public class Loops {     public static void main(String[] args)     {         ArrayList<Integer> ar = new ArrayList<>();//we will see about list in the next lessons         for (int i = 0; i < Integer.MAX_VALUE; i++)         {             ar.add(i);         }     } }