How to take the factorial of such a big number?
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@dheerajk_7 You have to find the factorial of very large numbers. You can’t store the factorials of 100, 200… for that you can use array which can store upto 10^6 size. Idea is to spilt the number into digits and to store each digit in the array and then perform actions digit wise. Try to find a logic. Let me know if you are not able to think about an approach.
Not getting how to do it>
Basic idea would be:
1.Create an array ‘res[]’ of MAX size where MAX is number of maximum digits in output.
2.Initialize value stored in ‘res[]’ as 1 and initialize ‘res_size’ (size of ‘res[]’) as 1.
3.Do following for all numbers from x = 2 to n.
……a) Multiply x with res[] and update res[] and res_size to store the multiplication result.
multiply(res[], x)
1.Initialize carry as 0.
2.Do following for i = 0 to res_size – 1
….a) Find value of res[i] * x + carry. Let this value be prod.
….b) Update res[i] by storing last digit of prod in it.
….c) Update carry by storing remaining digits in carry.
3.Put all digits of carry in res[] and increase res_size by number of digits in carry.
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