package tree;

import java.io.*;

import java.util.*;

public class Main{

private int n; //器官

private float k1;

private float k2;

private float k;

private float weight;

private String stopGrowing="1";

public Main(){}

public Main(int n, float k1, float k2, float k, float weight){

this.n = n;

this.k1 = k1;

this.k2 = k2;

this.k = k;

this.weight = weight;

}

private String grow(){

int day = 1;

while(weight <= k){

if((k1+k2) <= 1){

stopGrowing = "inf";

break;

}

weight *= (k1 + k2);

stopGrowing = day + "";

day++;

}

return stopGrowing;

}

public static void main(String[] args){

List<String> out = new ArrayList<String>();

String s;

int T = 0;

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

try{

s = br.readLine();

T = Integer.valueOf(s);

}catch(IOException e){

e.printStackTrace();

}

for(int i=1; i<=T; i++){

String[] baseInfoList;

String[] organWeightList;

float firstDayWeight = 0;

try{

s = br.readLine();

baseInfoList = s.split(" ");

s = br.readLine();

organWeightList = s.split(" ");

for(int j=0; j<organWeightList.length; j++){

firstDayWeight += Float.valueOf(organWeightList[i]);

}

Main cat = new Main(Integer.valueOf(baseInfoList[0]),

Float.valueOf(baseInfoList[1]),

Float.valueOf(baseInfoList[2]),

Float.valueOf(baseInfoList[3]),

firstDayWeight);

out.add(cat.grow());

}catch(IOException e){

e.printStackTrace();

}

}

for(int i=1; i<=T; i++){

System.out.println("Case #" + i + ":" + out.get(i-1));

}

}

}