Graphical User Interface : XOR encryption using c++

This is the GUI for command line xor encryption utility i shared before .


This program uses WIN 32 API to present a Graphical way for user to interact with the program instead of command line i used in an earlier post  there is no main window in this program it is driven by message menu's . This time it can encode all characters this code is still to pass many test before it becomes stable so if you find any serious bugs  here please comment about it below

here is the exe build for this encryption program for windows environment or download from sourceforge 

or you can check out the git hub repository here for the source code .
download executable for windows here

A Method to approximate Pi

This method is called Monte carlo simulation  it is a class of computer algorithm that aggregates data from a random sampling then uses laws of probability to find out some meaningful result  from the Data.

The basic idea is simple 

1-Draw a semicircle with radius r=1.00

2-And make a square of side 1 units coinciding with the circle .

3-Now randomly (uniformly ) throw some darts onto this arrangement .

4-Finally count the number of darts inside the circle(Nin) and total no of darts thrown (Ntot)

  now we know from the laws of probability that  P(Nin) = area of circular region divided by total  area of  the square , which comes to be Pi/4=Nin/Ntot

 hence Pi can be calculated by Pi = 4*(Nin/Ntot)

How do we implement this in a program ?

1 -Assume 2 axes x & y of 1000 units each .

2- Make a circle with origin as the center . and a square as shown earlier 

3- Define two variables x and y :

                  and call for a random value between 0 and 1000 for both of them separately (x,y)

4- Find the distance of this point from the origin if this distance is less than 1000 then the point is inside the circle.

5-Count the numbers of inside throws and divide by Total no of throws which was 1000 here multiply this by 4 for the value of PI π

#include<stdio.h> #include<stdlib.h> #include<math.h> int main(void) { int throws,cntin=0; scanf("%d",&throws); int temp=throws; while(throws--) { int a=rand()%1000; int b=rand()%1000; int c=(int)(sqrt(a*a+b*b)); if(c<1000) cntin++; } float ans=((4.000*cntin)/temp); printf("%0.02f \n",ans); }

or download code from here

But Its more interesting like this , if you like code golfing  

#include<namit.h>
#include <stdio.h>
main()
{
    long int d = 1;
    double p = 1;
    for(;;){printf("%.20f\n",(p+=((d-1)%4)?(1.0/(d+=2)):-1.0/(d+=2))*4);}