Why the output is 25 for the input :
n=55, m=20, x=2, y=1
Winning CB Scholarship
as with 20 discount coupons you have you can give scholarship to 10 students as x=2, now if 30 students performs badly you will get 30 discount coupon which can be used to give scholarship to remaining 15 students this total students getting scholarship are 10+15
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How do we know that 30 students performed badly, it is not given anywhere?
you need to find maximum number of students who can get scholarship so you can consider any possiblity , any combination of student passing or failing , if 30 students fail we can have 25 students to get scholarship , this provides the best situation for us
But why didn’t the same happen in case of n=10, m=3,x=1,y=1; we could have given 3 scholarships to 3 students and then 10-3=7, it means 7 students failed and we can give scholarships to 7 more students?
you only have 10 students so if you give scholarship to 3 students and fail 7 students then you don’t students to given scholarship
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