#include<stdio.h>
#include<conio.h>
void main()
{
    int i,n,sum;
    sum=0;
    clrscr();
    printf("Enter the Number : ");
    scanf("%d",&n);
    for(i=1; i<=n; i++)
    {
        if(i%2!=0)
            sum=sum+i;
    }
    printf("Sum of all ODD Integers is %d",sum);
    getch();
}

 OUTPUT:

Enter the Number : 10
Sum of all ODD Integers is 25