Describe precedence and associativity of operators with example

Question: Describe precedence and associativity of operators with example.

Precedence of operators:

   If more than one operators are involved in an expression, C language has a predefined rule of priority for the operators. This rule of priority of operators is called operator precedence.

   In C, precedence of arithmetic operators( *, %, /, +, -) is higher than relational operators(==, !=, >, <, >=, <=) and precedence of relational operator is higher than logical operators(&&, || and !).

Example:

(1 > 2 + 3 && 4)
This expression is equivalent to:
((1 > (2 + 3)) && 4)
i.e, (2 + 3) executes first resulting into 5
then, first part of the expression (1 > 5) executes resulting into 0 (false)
then, (0 && 4) executes resulting into 0 (false)

Output:

0

Associativity of operators:

   If two operators of same precedence (priority) is present in an expression, Associativity of operators indicate the order in which they execute.

Example:

1 == 2 != 3

   Here, operators == and != have same precedence. The associativity of both == and != is left to right, i.e, the expression on the left is executed first and moves towards the right.

Thus, the expression above is equivalent to:

((1 == 2) != 3)
i.e, (1 == 2) executes first resulting into 0 (false)
then, (0 != 3) executes resulting into 1 (true)

Output:

1