Any ideas why?

#include <iostream.h>
void main()
{
long int num, subnum[101], i, j, calc=0, temp, result=0;
cin>>num;
calc=num;
for (i=0;i<num;i++) cin>>subnum[i];
if (num=1)
cout<<(subnum[0]+1)/2;
else
for (i=num-1;i>0;i--) {
        for (j=num-1;j>num-i-1;j--)
        if (subnum[j]<subnum[j-1]) {
                temp=subnum[j-1];
            subnum[j-1]=subnum[j];
            subnum[j]=temp;
        };
        calc--;
        result+=(subnum[num-i-1]+1)/2;
        if (calc*2<num) {
            cout<<result;
            break;
        }
    }
}

> Any ideas why?
>
> #include <iostream.h>
> void main()
> {
> long int num, subnum[101], i, j, calc=0, temp, result=0;
> cin>>num;
> calc=num;
> for (i=0;i<num;i++) cin>>subnum[i];
> if (num=1)
> cout<<(subnum[0]+1)/2;
> else
> for (i=num-1;i>0;i--) {
>         for (j=num-1;j>num-i-1;j--)
>         if (subnum[j]<subnum[j-1]) {
>                 temp=subnum[j-1];
>             subnum[j-1]=subnum[j];
>             subnum[j]=temp;
>         };
>         calc--;
>         result+=(subnum[num-i-1]+1)/2;
>         if (calc*2<num) {
>             cout<<result;
>             break;
>         }
>     }
> }
>
>