Enhanced for-loop problem

[Deepak Bajoria]

Hello Ranchers,

This code:

int []arr = {1,2,3,4};
for ( int i : arr )
{
   arr[i] = 0;
}
 
for ( int i : arr )
{
   System.out.println(i);
}

compiles successfully produces the output:
0
0
3
0


I am totally puzzled about it.

As per my understanding...In the first loop values of i is set to 1,2,3,and 4. Therefore it tries to access these the positions: arr[1],arr[2],arr[3]and arr[4]. But when it tries to access arr[4] it should throw ArrayIndexOutOfBoundsException because arr has only 4 elements.

Even if it could access them, the output should have been 0 0 0 0 and not 0 0 3 0 as they all are being set to 0 in the 1st loop. From where does that 3 persists?


Thanks

[Mihai Fonoage]

Hi Deepak,

Please search this forum for the problem you mentioned has been already discussed in detail.

Mihai Fonoage

[Milan Sutaria]

what mihai said is true

[Sagar Rohankar]

Sorry folks, I am not able to find out that already discussed thread, Please anybody put some pointer to that thread !

[Pankaj Mittal]

check out

https://coderanch.com/t/269503/java-programmer-SCJP/certification/Arrays

[Deepak Bajoria]

Hats off to this forum......I find all questions I stuck upon has already been discussed here. Great site.