#include  <stdio.h>
#include  <conio.h>

void main()
{
 int x=0,y=0,n;
 clrscr();
 printf("Enter the value of n : ");
 scanf("%d",&n);
 while(x<=n)
 {
   y+=x;
   x+=2;
 }
 printf("summation of even no up to given no is %d",y);
 getch();
 }