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coperator-precedence

Precedence of C operators

I am new in programming I have started learning with C. I wanted to learn about the precedence of the operators in the following 

if ( p == 2 || p % 2 )

Please help me.

Solution

  • Here

    if ( p == 2 || p % 2 )

    it looks like

    if( operand1 || operand2)

    where operand1 is p == 2 and operand2 is P % 2. Now the logical OR || truth table is

    operand1  operand2  operand1 || operand2
0         0         0
0         1         1
1         0         1
1         1         1

    From the above table, it's clear that if the first operand operand1 result is true then the result will always true & second operand operand2 doesn't get evaluated.

    operand1 is ==>

    • p == 2 (lets assume p is 2)

    • 2 == 2 results in true hence operand2 doesn't get evaluated and if blocks looks like as

      if(true) { }

    Lets assume p is 3 then operand1 i.e 2 == 3 is false i.e operand2 gets evaluated i.e 3%2 i.e 1 that means if blocks looks like

    if(true)
{
}

    Let's assume p is 4 then operand1 i.e 2 == 4 is false i.e operand2 gets evaluated i.e 4%2 i.e 0 that means if blocks looks like

    if(false)
{
}

    Hope the above explanation makes sense to you.

    About the associativity and precedence, please look into manual page of operator