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Write a function that returns n-1 for an input of n

Sat, 08/26/2006 - 08:59 — Pooja

Write a function that takes n as that input and returns the value n-1.. The trick is to not use the - sign.. How many differnet ways can you do this?

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Sun, 09/10/2006 - 17:51 — geekgod

Write a function that returns n-1 for an input of n

These will work only if the machine/os supports 2's complement arithmetic operations..

Sun, 09/10/2006 - 14:35 — sathish_kumar

Write a function that returns n-1 for an input of n

it's pretty simple..

find the one's complement of n add 1 to it and again find the complement of the number, u will get n-1...

int value(int n)
{
int n1;
n1 = (~n) + 1 ;
return (~n1);
}

hope this is correct..

Mon, 08/28/2006 - 05:17 — digitalp

Write a function that returns n-1 for an input of n

If it is a two's compliment machine the following shoud work
[code:1]int nminus1(int n)
{
return n+(~0);
}[/code:1]

when you flip all bits in 0 using ~ operator you get -1 (all bits are now 1), only in a two's compliment machine (pretty much all the machines out there :)). add that to n and you have n-1