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Dount in K&B exam question

 
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I dont get how the output is 'Good'. In this code we are passing an array and a comparator to the Arrays.sort() which will call the compare method and in there we are reversing order but I dont quite get the process of it.(Im a little confused with what charAt() is doing.). Are we reversing order based on 2nd character of GOod with that of bAd and uGly?? Can someone give me a step by step of how the o/p of 'good' is being achieved.
 
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If compare() method returns negative number, it means s1 < s2

When comparator compares "Good" and "Bad". s1 = "Good" and s2 = "Bad"

i.e., "Good" will be assigned to s1 and "Bad" to s2.

s2.charAt(1) will give you 'a'

s1.chatAt(1) will return 'o'

ASCII equivalent of 'a' is 97 and that of 'o' is 111. So difference i.e., 'a' - 'o' is negative.

Since number is negative, therefore s1 is less than s2. (No sorting)

Second case is the comparison between "Bad" & "Ugly".

Again s2.chatAt(1) is 'g' and s1.chatAt(1) is 'a'

'g' - 'a' is positive and g comes after a in ASCII characters. So difference is going to be positive number. It means here s1 > s2

Therefore after sorting, the array will be {"Good", "Ugly", "Bad"}



Naseem
 
Amit Batra
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hmm...I kinda get it now..thanks naseem
 
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