# Rules of Operator Precedence in C Language

3. The associativity and priority of the ++ prefix and the ++ postfix are very different from each other. Here, the priority of the ++ prefix is lower than the ++ postfix. Thus, their associativity is also different. Here, the associativity of the ++ prefix is from right to left, while the associativity of Postfix++ is from left to right. 2. All operators that have a similar order of priority have the same associativity. This is very important, otherwise the compiler cannot decide the order of evaluation that an expression should follow if it has two operators with the same priority but a different associativity. For example, – and + have the same associativity.

Answer: This results in a compilation error. Java parses it as ++(++x). The term ++x increases the variable x and gives rise to the integer 11. This results in a compilation error because the preincrement operator must be applied to a variable (not an integer). Thus, although the preincrement operator has right-to-left associativity, this property is not useful. Please don`t be confused after seeing the table above. They are all used in a different situation, but not all at the same time. For the solution of the basic equation, we consider only the priority of the following operators.

Operator priority determines which operator runs first in an expression with multiple operators of different priority. Example: Solve The point to note here is that associativity is not applicable when we define the evaluation order of operands with different rankings. Operators that are in the same cell (multiple operator rows can be listed in a cell) are evaluated with the same priority in the specified direction. For example, the expression a=b=c is analyzed as a=(b=c) rather than (a=b)=c due to right-to-left associativity. Example: x = 7 + 3 * 2; Here, x is assigned to 13, not 20, because the * operator has a higher priority than +, i.e. first multiplied by 3*2 and then added to 7. 1) Associativity is only used when there are two or more operators with the same priority. Note that associativity does not define the order in which operands of a single operator are evaluated. For example, consider the following program, the associativity of the + operator is left to right, but this does not mean that f1() is always called before f2(). The output of the next program actually depends on the compiler. More information is available here.

Here, operators with the highest priority appear at the top of the table, operators with the lowest at the bottom. In an expression, operators with a higher priority are evaluated first. The priority of operators determines which operator executes first if there are multiple operators in an expression. Most Java operators are associative from left to right. A notable exception is the assigment operator, which is associative from right to left. Therefore, the expression x = y = z = 17 is treated as x = (y = (z = 17)), where all three variables are set to 17. Keep in mind that an assignment statement evaluates the value on its right side. Associativity is not relevant for some operators. For example, x and x++- are invalid expressions in Java.

It is good to know the rules of priority and associativity, but it is better to use parentheses, especially for less commonly used operators (operators other than +, -, *., etc.). Parentheses increase the readability of the code because the reader does not need to see the table to determine the order. We can calculate the output of this code using the ranking table. According to this table, the priority of the mapping operator ( – ) and the addition operator ( + ) is lower than that of the multiplication operator ( * ). Therefore, multiplication is evaluated here first. 5. We don`t have a comparison concatenation in the C programming language. Python processes expressions such as x > y > z as x > y and y > z. There is no similar type of concatenation in program C. The priority of operators determines the grouping of terms in an expression and decides how an expression evaluates. Some operators have a higher priority than others; For example, the multiplication operator has a higher priority than the addition operator. The evaluation of this expression would be (30 * 2) / 12, since the associativity for the two operators – multiplication and division – goes from left to right.

The associativity of the operators determines the direction in which an expression is evaluated. For example, when you parse an expression, an operator listed on one row is bound more closely (such as in parentheses) to its arguments than any operator listed on a line below. For example, the expression *p++ is parsed as *(p++) rather than (*p)++. Answer: 3abc or abc12. The + operator is associative from left to right, whether it is a concatenation of strings or an addition of strings. 4. We must use a comma (,) very carefully, because it has the lowest priority among all other operators present in an expression. The associativity specification is redundant for unary operators and is displayed only for completeness: unary prefix operators always associate from right to left (sizeof ++*p is sizeof(++(*p))) and unary postfix operators always from left to right (a[1][2]++ is ((a[1])[2])++).