Bhaiya, in this video at 05:39
In line 15, lb = lower_bound() - coins -1;
Then it returned index 6 and value 100. This should be the case without subtracting -1.
why we did -1 ?? We have already written comparator which will give us <= value
Money Change Problem
@Neeta hi ,you are right woh bhaiya ne galti se likh dia ,agr apne apna comparator bnaya hai to -1 ki jaroorat nhi hai 
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