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fsbadr
Jun23-08, 02:49 PM
1. The problem statement, all variables and given/known data
folks,

I have a small problem understanding a function as to what its doing:

I have run this program in C++. I will comment the lines of code as per my understanding. Your insight would be useful

unsigned int myfunc(unsigned int n)
{
// for n here I took 1200

unsigned int temp =
//logical shift done here as it is unsigned, division for 1200 came to 0 as it was rounded
(n >> 24) |

// logical shift as well, logical and operation with hex value, result is 262144
((n << 8) & 0x00FF0000) |

// logical shift as well, logical and operation with hex value, came to 0 as it is rounded
((n >> 8) & 0x0000FF00) |

// computes to 2952790016
(n << 24);

//temp is then the sum of all operations which in this case is 0 + 262144 + 0 + 2952790016 totaling 2953052160.
return temp;

the value returned is the sum of all operations.

}

thanks for your help.

2. Relevant equations

This is a real world scenario function, what is it doing?

3. The attempt at a solution

In part (a), I have put in my findings at attempting the solution.
1. The problem statement, all variables and given/known data



2. Relevant equations



3. The attempt at a solution

D H
Jun23-08, 03:07 PM
You will see what it is doing much easier if you express the input and output in hexadecimal rather than decimal format.