uva 11689 soda

#include<stdio.h>
int main()
{
    long long t,i,e,f,c,a,b,g,d,sum;
    while(scanf("%lld",&t)==1)
    {
        for(i=1;i<=t;i++)
        {
            scanf("%lld%lld%lld",&e,&f,&c);
            sum=0;
            a=e+f;
            while(a>=c)
            {
                b=a/c;
                d=a%c;
                g=b+d;
                a=g;
                sum=sum+b;

            }
            printf("%lld\n",sum);
        }
    }
    return 0;
}