Help needed to print the value nth number raised to the power n.

Rajdeep_

Hello People, I am quite a newbie to C++ programming and I got stuck up with a simple program. The program requires me to print the value for 2 raised to the power 20. I actually had the idea creeping about this program since 1 megabyte is 2 raised to the power 20. I wanted to find the result of that via this piece of code:

#include
#include
int main()
{
int a=2;
for (int i=2; i<=20; i++)
{
a=a*a;
}
cout<

and the output I get is: 0

The compiler/IDE I'm using is Borland C++ (latest version) but I know theres nothing wrong with the compiler though. There must be some logical mistake. Rectification would be appreciated folks. Hoping for help.

Thanks!
Rajdeep_

Lost User

You are not raising it to the 20th power, you are repeatedly squaring the value, The first time through the loop you get 4 (2*2), then 16 (4*4), then 256 (16*16), and so on.

Use the best guess

Rajdeep_

Thank you. I will work on that part.

V J NAGA VARA PRASAD

a is a integer data type :) .you are printing the value by multiplying it 19 times and which in return it exceeds more than LONG data type :sigh: .hence your output is always zero :doh: . There is no compiler problem. :) I think you got what I am explaining you. :omg:

Vaclav_

int x,total = 1 ; for(x=0; x<20; x++){ total += 1<

Lost User

total = 1<<20;

Use the best guess

David Crow

You need to multiply a by 2 twenty times. Something like:

int a = 1;
for (int i = 0; i < 20; i++)
a = a * 2;

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