Missing and Repeated :Vinisha Ma'am

in array there are numbers only upto n
one is repeated and one is missing
find both the numbers

use the following method:

mark the missing number as M and the duplicated as D

1) compute the sum of regular list of numbers from 1 to N call it RegularSum

2) compute the sum of your array (the one with M and D) call it MySum

now you know that MySum+M-D=RegularSum

this is one equation.

the second one uses multiplication:

3) compute the multiplication of numbers of regular list of numbers from 1 to N call it RegularMultiplication

4) compute the multiplication of numbers of your list (the one with M and D) call it MyMultiplication

now you know that MyMultiplication=RegularMultiplication*D/M

at this point you have two equations with two parameters, solve and rule!

sexy Ramp...mast solution..

your case fails when sum/multiplication exceed the integer limit there exists better solutions for it

as the numbers are upto n we can use count sort ..
in the array that saves the number of occurences of each number
1. value of count for the repeated number will be 2 and
2. for the missing number will be zero.

this is very popular interview question, the actual version goes like.
1) no Auxillary space(map,array etc) to be used.
2)O(n) time complexity.

LIMIT EXCEEDED:i agree that the limit might exceed.but this is the answer the interviewer is expecting from us.
NO MAPS:so map etc cannot be used.and for questions like that it is a trivial ans,not much impressive.for that matter take the question from subjective paper.that was solved by XOR,not by maps.

yes one solution is we can solve it by xor
but explain to karo ramu bhai


there exist a solution without xor also which even doesn't use single extra variable

xor se kaise karoge bhaiya?? batao