import java.io.PrintStream;

import java.util.*;

/**

* Codejam 2012 Round 3

* Problem C. Quality Food

* Only small solved.

*/

public class Main {

public String solve(Scanner scanner) {

return solveSmall(scanner);

}

class Meal {

long price, time;

public Meal(long _price, long _time) {

price=_price; time=_time;

}

}

private String solveSmall(Scanner scanner) {

long m=scanner.nextLong(), f=scanner.nextLong();

int n=scanner.nextInt();

Meal[] meals=new Meal[n];

for (int i=0;i<n;i++) {

meals[i]=new Meal(scanner.nextLong(), scanner.nextLong());

}

ArrayList<Long> list=new ArrayList<>();

list.add(0L);

for (int i=0;;i++) {

long last=i==0?f:list.get(i);

long p=Long.MAX_VALUE;

for (Meal meal: meals) {

if (meal.time>=i && meal.price<p) {

p=meal.price;

}

}

if (p==Long.MAX_VALUE) break;

list.add(last+p);

if (last+p>m) break;

}

long mx=0;

for (int i=1;i<list.size()-1;i++) {

mx=Math.max(mx, cal(list.get(i), list.get(i+1), i, i+1, m));

}

return String.valueOf(mx);

}

private long cal(long u, long v, long a, long b, long m) {

long mx=0;

for (long x=0;u*x<=m;x++) {

long l=m-u*x, y=l/v;

mx=Math.max(mx, a*x+b*y);

}

return mx;

}

public static void main(String[] args) throws Exception {

System.setOut(new PrintStream("output.txt"));

Scanner scanner=new Scanner(System.in);

int times=scanner.nextInt();

long start=System.currentTimeMillis();

for (int t=1;t<=times;t++) {

try {

System.out.println(String.format("Case #%d: %s", t, new Main().solve(scanner)));

}

catch (Throwable e) {

System.err.println("ERROR in case #"+t);

e.printStackTrace();

}

}

long end=System.currentTimeMillis();

System.err.println(String.format("Time used: %.3fs", (end-start)/1000.0));

}

}