partial submission on hacker rank : <p>why is my code <a href="http://ideone.com/zm6hP7" rel="nofollow">http://ideone.com/zm6hP7</a>  not satisfying all test cases in the problem <a href="https://www.hackerrank.com/contests/opc-a/challenges/infinite-series" rel="nofollow">https://www.hackerrank.com/contests/opc-a/challenges/infinite-series</a>  ?
I have downloaded unsatisfied test cases and still can't find any problem in my code....can somebody tell me what the problem is???</p>

<pre><code>#include&lt;stdio.h&gt;`
#define m 1000000007
int main()
{
long long int t;
scanf("%lld",&amp;t);
for(long long int i=0;i&lt;t;i++)
{
    long long int l,r;
    scanf("%lld %lld",&amp;l,&amp;r);
    long long int x,y;
    if(l%2==0)
        x=(((l/2)%m)*((l-1)%m))%m;
    else
        x=((l%m)*(((l-1)/2)%m))%m;
    if(r%2==0)
        y=(((r/2)%m)*((r+1)%m))%m;
    else
        y=((r%m)*(((r+1)/2)%m))%m;
    printf("%lld\n",y-x);
}
return 0;
}
</code></pre>
