For some reason in many American cartoons anvils fall from time to time onto heroes' heads. Of course, safes, wardrobes, cruisers, planes fall sometimes too... But anvils do so most of all.

Anvils come in different sizes and shapes. Quite often they get the hero stuck deep in the ground. But have you ever thought who throws anvils from the sky? From what height? We are sure that such questions have never troubled you!

It turns out that throwing an anvil properly is not an easy task at all. Let's describe one of the most popular anvil throwing models.

Let the height p of the potential victim vary in the range [0;a] and the direction of the wind q vary in the range [ - b;b]. p and q could be any real (floating) numbers. Then we can assume that the anvil will fit the toon's head perfectly only if the following equation has at least one real root: 

<image>

Determine the probability with which an aim can be successfully hit by an anvil.

You can assume that the p and q coefficients are chosen equiprobably and independently in their ranges.

Input

The first line contains integer t (1 ≤ t ≤ 10000) — amount of testcases.

Each of the following t lines contain two space-separated integers a and b (0 ≤ a, b ≤ 106).

Pretests contain all the tests with 0 < a < 10, 0 ≤ b < 10.

Output

Print t lines — the probability of a successful anvil hit for each testcase. The absolute or relative error of the answer should not exceed 10 - 6.

Examples

Input

2
4 2
1 2


Output

0.6250000000
0.5312500000
/*Talent is something you make bloom , instinct is something you polish*/
import java.io.*;
import java.math.*;
import java.util.*;
public class Main
{
    static long mod=((long)1e9)+7;//toString
    public static int gcd(int a,int b){if(b==0)return a;else return gcd(b,a%b);}
    public static long pow_mod(long x,long y){long res=1;x=x%mod;while(y > 0){if((y & 1)==1)res=(res * x)%mod;y=y>>1;x =(x * x)%mod;}return res;}
    public static int lower_bound(int[]arr,int val){int lo=0;int hi=arr.length-1;while(lo<hi){int mid=lo+((hi-lo+1)/2);if(arr[mid]==val){return mid;}else if(arr[mid]>val){hi=mid-1;}else lo=mid;}if(arr[lo]<=val)return lo;else return -1;}
    public static int upper_bound(int[]arr,int val){int lo=0;int hi=arr.length-1;while(lo<hi){int mid=lo+((hi-lo)/2);if(arr[mid]==val){return mid;}else if(arr[mid]>val){hi=mid;;}else lo=mid+1;}if(arr[lo]>=val)return lo;else return -1;}
    
    public static void main (String[] args) throws java.lang.Exception
    {
        Reader sn = new Reader();
        Print p = new Print();
        int t = sn.nextInt();
        while(t-- > 0){
        int a = sn.nextInt();
        int b = sn.nextInt();
        if(a == 0 && b == 0)
        p.printLine("1");
        else if(b == 0)
        p.printLine("1");
        else if(a == 0)
        p.printLine("0.5");
        else if(a >= 4*b)
        p.printLine(Double.toString(1.00 - (((double)b)/((double)a))));
        else
        p.printLine(Double.toString(0.5 + (((double)a)/(16.00 * ((double)b)))));
        }
        p.close();
    }
}
class Pair implements Comparable<Pair> {
		int val;
		int in;
		Pair(int a, int b){
			val=a;
	        in=b;
		}
		@Override
		public int compareTo(Pair o) {
			if(val==o.val)
			return Integer.compare(in,o.in);
			else
			return Integer.compare(val,o.val);
		}}
class Reader
    {
        final private int BUFFER_SIZE = 1 << 16;
        private DataInputStream din;
        private byte[] buffer;
        private int bufferPointer, bytesRead;
        public boolean isSpaceChar(int c) { return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; }
        public Reader()
        {
            din = new DataInputStream(System.in);
            buffer = new byte[BUFFER_SIZE];
            bufferPointer = bytesRead = 0;
        }
 
        public Reader(String file_name) throws IOException
        {
            din = new DataInputStream(new FileInputStream(file_name));
            buffer = new byte[BUFFER_SIZE];
            bufferPointer = bytesRead = 0;
        }
 
        public String readLine() throws IOException
        {
            byte[] buf = new byte[64]; // line length
            int cnt = 0, c;
            while ((c = read()) != -1)
            {
                if (c == '\n')
                    break;
                buf[cnt++] = (byte) c;
            }
            return new String(buf, 0, cnt);
        }
        
        public String readWord()throws IOException
        {
		int c = read();
		while (isSpaceChar(c)) c = read();        
		StringBuilder res = new StringBuilder();
		do {
			res.appendCodePoint(c);
			c = read();
		}while (!isSpaceChar(c));
		return res.toString();
	    } 
	
        public int nextInt() throws IOException
        {
            int ret = 0;
            byte c = read();
            while (c <= ' ')
                c = read();
            boolean neg = (c == '-');
            if (neg)
                c = read();
            do
            {
                ret = ret * 10 + c - '0';
            }  while ((c = read()) >= '0' && c <= '9');
 
            if (neg)
                return -ret;
            return ret;
        }
 
        public long nextLong() throws IOException
        {
            long ret = 0;
            byte c = read();
            while (c <= ' ')
                c = read();
            boolean neg = (c == '-');
            if (neg)
                c = read();
            do {
                ret = ret * 10 + c - '0';
            }
            while ((c = read()) >= '0' && c <= '9');
            if (neg)
                return -ret;
            return ret;
        }
 
        public double nextDouble() throws IOException
        {
            double ret = 0, div = 1;
            byte c = read();
            while (c <= ' ')
                c = read();
            boolean neg = (c == '-');
            if (neg)
                c = read();
 
            do {
                ret = ret * 10 + c - '0';
            }
            while ((c = read()) >= '0' && c <= '9');
 
            if (c == '.')
            {
                while ((c = read()) >= '0' && c <= '9')
                {
                    ret += (c - '0') / (div *= 10);
                }
            }
 
            if (neg)
                return -ret;
            return ret;
        }
 
        private void fillBuffer() throws IOException
        {
            bytesRead = din.read(buffer, bufferPointer = 0, BUFFER_SIZE);
            if (bytesRead == -1)
                buffer[0] = -1;
        }
 
        private byte read() throws IOException
        {
            if (bufferPointer == bytesRead)
                fillBuffer();
            return buffer[bufferPointer++];
        }
 
        public void close() throws IOException
        {
            if (din == null)
                return;
            din.close();
        }
    }
class Print
{
    private final BufferedWriter bw;
    public Print()
    {
        bw=new BufferedWriter(new OutputStreamWriter(System.out));
    }
    public void print(String str)throws IOException
    {
        bw.append(str);
    }
    public void printLine(String str)throws IOException
    {
        print(str);
        bw.append("\n");
    }
    public void close()throws IOException
    {
        bw.close();
    }}