👋Java Basics & I/O Programs

Adds two fixed integers and prints the result.

Finds a person's age in years from their birth year and the current year.

Computes the area of a circle from its radius using the formula π × r².

Computes the area of a rectangle from its length and width.

Computes the area of a triangle from its base and height.

Finds the average of a handful of individual numbers, without using an array or a loop.

Computes body mass index from weight and height, then labels it with its category.

Computes the circumference of a circle from its radius using the formula 2 × π × r.

Computes a discount amount by applying a single flat discount percentage to a price.

Computes an electricity bill by multiplying units consumed by a single flat rate per unit.

Computes gross salary by summing basic pay, HRA, DA, and other fixed allowances.

Computes what percentage one value is of another, such as marks obtained out of total marks.

Computes the perimeter of a rectangle from its length and width.

Finds the remainder left over when one integer is divided by another.

Computes pay by multiplying an hourly rate by the number of hours worked.

Computes simple interest from a principal amount, annual rate, and time in years.

Converts a temperature from Celsius to Fahrenheit using the standard formula.

Shows the two meanings of char-to-int conversion: a character's code versus a digit's numeric value.

Converts a temperature from Fahrenheit to Celsius using the standard formula.

Compares three common ways of turning an int into a String and checks that they agree.

Converts a distance from kilometers to miles using the standard conversion factor.

Converts a distance from miles to kilometers using the standard conversion factor.

Parses text into an int with Integer.parseInt, handling input that isn't a valid number.

Applies each arithmetic operator — plus, minus, times, divide, and modulo — to the same two numbers.

Applies the simple and compound assignment operators to the same variable, step by step.

Applies the bitwise AND operator to two integers and shows the result at the bit level.

Applies the bitwise NOT (complement) operator to an integer and explains why the result is negative.

Applies the bitwise OR operator to two integers and shows the result at the bit level.

Applies the bitwise XOR operator to two integers and shows the result at the bit level.

Applies the left shift operator to an integer and shows how each shift doubles its value.

Applies the logical AND, OR, and NOT operators to two boolean values.

Applies each relational operator to the same two numbers and prints the boolean result.

Applies the signed right shift operator to a negative integer and shows how the sign bit is preserved.

Uses the ternary operator to pick the larger of two numbers in a single expression.

Applies unary plus, unary minus, and pre/post increment and decrement to a single variable.

Divides one fixed integer by another and prints the result.

The first program every Java developer writes.

Multiplies two fixed integers and prints the result.

Prints several lines of text to the console.

Stores a name in a variable and prints it to the console.

Reads a single decimal number typed by the user and prints it back.

Reads a single integer typed by the user and prints it back.

Reads an int, a double, and a String from the console in a single program.

Reads a full line of text typed by the user and prints it back.

Subtracts one fixed integer from another and prints the result.

Reads two integers from the console and prints their sum.

Swaps the values of two integers using a temporary third variable.

Swaps the values of two integers without using any extra storage.

Computes compound interest from a principal, annual rate, and time, using Math.pow() to raise the growth factor to a power.

Evaluates a mixed expression step by step to show the order Java applies different operator types in.

Breaks a total day count down into whole years, whole months, and leftover days.

Breaks a total second count down into whole hours, whole minutes, and leftover seconds.

Proves that && skips evaluating its right-hand side entirely once the left side is already false.

Proves that || skips evaluating its right-hand side entirely once the left side is already true.

Applies the unsigned right shift operator to a negative integer and contrasts it with the signed right shift.