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Operator Precedence

()   []
++(postfix)  --(postfix)
left to right HIGH
right to left
++(prefix)    --(prefix)
!   +(unary)  -(unary)  *   &
left to right
right to left
*   /   %left to right MEDIUM
+(binary) -(binary)left to right
<   <=   >   >=left to right
==   !=left to right
&&left to right
||left to right
=  +=  -=  *=   /=   %=right to left
?:right to left LOW
,left to right

Unary +, - and * have higher precedence than the binary forms. The operator () refers to function call.

Precedence determines the order in which operands are bound to operators. Operators on the same line have the same precedence; rows are in order of decreasing precedence. C does not specify the order in which the operands of an operator are evaluated. Similarly, the order in which function arguments are evaluated is not specified. Examples:

// Example-1:x = f() + g();                         
// Example-2:a[i] = i++;
// Example-3:printf("%d %d\n",++n,power(2,n));      
// Example-4:z = x / ++x;

Programs should not depend upon the order of evaluation of expressions, except as guaranteed by ANSI C for the following operators:

 1.  a, b           comma operator (not the comma between arguments)  2.  a && b         logical and 3.  a || b         logical or 4.  a ? b : c      conditional 

All of these guarantee that expression a will be computed before expression b (or c).

In addition, when a function-call takes place all arguments are evaluated before control transfers to the function.

5.  a(b)           function call 

ANSI C++ guarantees that each full expression will be evaluted before going on.

6.  each full expression