Question

For example,

int result;

result = 125/100;

or

result = 43/100;

Will result always be the floor of the division? What is the defined behavior?

Answer 1

Will result always be the floor of the division? What is the defined behavior?

Not quite. It truncates toward 0, rather than flooring.

6.5.5 Multiplicative operators

6 When integers are divided, the result of the / operator is the algebraic quotient with any
fractional part discarded.⁸⁸⁾ If the quotient a/b is representable, the expression
(a/b)*b + a%b shall equal a.

and the corresponding footnote:

88. This is often called ‘‘truncation toward zero’’.

Of course two points to note are:

3 The usual arithmetic conversions are performed on the operands.

and:

5 The result of the / operator is the
quotient from the division of the
first operand by the second; the
result of the % operator is the
remainder. In both operations, if the
value of the second operand is zero,
the behavior is undefined.

[Note: Emphasis mine]