*

[Arithmetic Operators]

説明

Multiplication is one of the four primary arithmetic operations. The operator * (asterisk) operates on two operands to produce the product.

Syntax

product = operand1 * operand2;

Parameters

product: variable. Allowed data types: int, float, double, byte, short, long.
operand1: variable or constant. Allowed data types: int, float, double, byte, short, long.
operand2: variable or constant. Allowed data types: int, float, double, byte, short, long.

Example Code

int a = 5;
int b = 10;
int c = 0;
c = a * b;  // the variable 'c' gets a value of 50 after this statement is executed

Tips

1. The multiplication operation can overflow if the result is bigger than that which can be stored in the data type.
2. If one of the numbers (operands) are of the type float or of type double, floating point math will be used for the calculation.
3. If the operands are of float / double data type and the variable that stores the product is an integer, then only the integral part is stored and the fractional part of the number is lost.

float a = 5.5;
float b = 6.6;
int c = 0;
c = a * b;  // the variable 'c' stores a value of 36 only as opposed to the expected product of 36.3

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