code crashes when int arr = 1 && arr; but not int arr = 0 && arr;

Question

Hi,

I wanted to know why the following code crashes.

int main( ) 
{  
    int arr = 1 && arr;
    return 0; 
}

BUT not with the below code

int main( ) 
{  
    int arr = 0 && arr;
    return 0; 
}

Thanks in advance

Answer 1

0 && arr
The above expression is false because of 0, so arr is not checked unlike 1 && arr where arr has to be checked to evaluate the value for expression.

---

You should try:

int main(){
  int a = 0 && printf("a"); //printf returns number of characters printed, 1
  int b = 1 && printf("b");
  return 0;
} 

Answer 2

Because of short circuit evaluation of boolean expressions. In the first example the left side of the && operator evaluates to true so the right is evaluated. In the second case the left is false so the right is never evaluated.