plz check my program...

#include<stdio.h>
#include<math.h>

int main()
{
    long n,a,p,x,chk=0,sum=0;
    scanf("%ld",&n);
    for(x=sqrt(n);chk==0;x++)
    {
        if(x*(x+1)/2>n)
        {
            break;
        }
    }
    for(chk=0;x<=n/2+1;x++)
    {
        for(p=1;sum<n;p++)
        {
            sum+=x+1-p;
            if(sum==n)
            {
                a=x+1-p;
                x=n/2+2;
                chk=1;
                break;
            }
        }
        sum=0;
    }
    if(chk==1) printf("%ld %ld",a,p);
    return 0;
}

Your source have some problem about sqrt fuction.
I think you have to use sqrt((double)n);