C :

#include <stdio.h>
 
int main()
 
{
    int a;
   float b;
    while(scanf("%d",&a) != EOF)
 {
 if (a==1) 
   b=0.5043;
 
    
  else if (a==0)
		b=0.0001;
        printf("p=%.4f\n",b);
		
}
    return 0;
}

C++ :

#include<iostream>
using namespace std;
int main(){
	int a;
	cin>>a;
	if(a==1)
	   cout<<"p=0.5043\n";
	else
   	   cout<<"p=0.0001\n";
	return 0;
}

Java :

import java.text.DecimalFormat;
import java.util.Scanner;

public class Main {
	public static void main(String[] args){
		
		float f[] = new float[2];
		Scanner reader = new Scanner(System.in); 
		int a;
		DecimalFormat df=new DecimalFormat("#0.0000");
		while(reader.hasNext()){
			a = reader.nextInt();
			if(a==1){
				f = null;
				f =new float[1];
				f[0]=(float)0.5043;	
			}
			else {
				f = null;
				f =new float[1];
				f[0] = (float) 0.0001;
			}
			for(int i=0;i<f.length;i++){
				System.out.println("p="+df.format(f[i]));
			}
		}
	}
}