```
  7 foreach (@crons) {
  8     unless (index($_, "cks") != -1) {
  9         unless (index($_, "aab") != -1) {
 10             unless (index($_, "lam") != -1) {
 11                 push (@found, $_);
 12             }
 13         }
 14     }
 15 }

```

how come the above does not give the same output as the following:

```
  7 foreach (@crons) {
  8     unless (index($_, "cks") != -1 && index($_, "aab") != -1 && index($_, "lam") != -1) {
  9         push (@found, $_);
 10     }
 11 }

```

@crons has the list of strings and I am trying to get all string that does not have "cks", "aab" and "lam" 

The first section of code does what i want but the second doesnt and in my mind, it should...  

Can anyone care to explain why they are not the same nor why it does not give the same output?