Form the biggest number problem

#1

https://ide.codingblocks.com/s/230407 please heck, this code is runnning fine for me but all test cases are getting failed?

#2

@rachitbansal2500
the correct comparator
bool compare(string a,string b){
return a + b > b+a; //return by which you get a bigger number.
}

#3

Hey! I don’t understand why is it so?

#4

think about “909” and “99”
99 < 909 yields true.
but we will put 99 first and then 909 to form the biggest number.

#5

But when we do string comparisons it’s always lexicographical hence a>b will actually yield 909<99

#6

image
image1920×1080 238 KB

#7

Test case that fails a>b is
1
3
9 990 909
we are not comparing lexicographically. and also to sort lexicographically we can use
bool compare(string a, string b) {

return lexicographical_compare(a.begin(), a.end(), b.begin(), b.end()); //return lexo smaller

}

1 Like
#8

Ok I do understand why lexicographical sort is not the correct option. But we can simply perform lexicographical sort using a>b in string comparisons right?

#9

Yes. we can do that.

1 Like
#10

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