Programming

Question

consider the foloowing program: 
int main()
{
  int var1=35, *var2,*var3;
  var2=&var1;//suppose address of var1 1006
  var3=var2;
  *var2++=*var3++;
  var1++;
  printf("var1=%d var2=%d var3=%d",var1,var2,var3);
  return0;
}

output print by above program ?

Answer 1

1. int main()
2. {
3. int var1=35, *var2,*var3;
4. var2=&var1;    //means var2 also ponts to var1
5. var3=var2;     // means var3 also point to var1
6. *var2++=*var3++;   //means value at var2 address will be replced by value at var3 address which is same i.e. 35 no change,  after that var2 and var3 adress is incermented means point to location which contain garbage i.e. 1010 , 1010
7. var1++;   // var1 value increament by 1 = var1= 36
8. printf("var1=%d var2=%d var3=%d",var1,var2,var3);  // 36 , 1010 ,1010 
9. since i aasume pointer take 4 Byte so 1006 +4 = 1010
10. return0;
11. }

Comments

output should be 36,1010,1010 rt?

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yeah , explain

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  *var2++=*var3++;

The var2 and var3 are inceremnted to point the next integer location which will be 1010 asuming that var2 and var3 contains 1006 before increment.

But before the incementation what is done here is assigment.Since post incement after the variable name var2 and var3..

During assigmnet ,the value at the address contained in var2 is replaced by the value at the address contained in var3.

And finally value of variable var1 is incremented to 36.

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ur assuming size of pointer is 4bytes rt?

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yes.

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*var2++=*var3++
here we are incrementing *var2 and *var3 //i.e. value at var2 or var3
So, why value at var2 or value at var3 not incremented
why address of that position is incremented?
is it for precedence of ++ is more than *?

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yes

http://www.difranco.net/compsci/C_Operator_Precedence_Table.htm