C :

#include "stdio.h"
 
int main()
{
    int a;
    float b;
    while(scanf("%d",&a) != EOF)
 {
 if (a==1)
   b=1.0/4;  
 else if (a==0)   
    b=0.20;
     printf("%.2f\n",b);	
 
  }
    return 0;
}

C++ :

#include <stdio.h> 
int main()
{
    int a;
    float b;
    while(scanf("%d",&a) != EOF)
 {if (a==1) b=0.25; //将“作业答案”替换为该题答案。若有多行，用多行重复输出。
 else if (a==0) 
b=0.20;    
   printf("%.2f\n",b);}
    return 0;
}

Java :

import java.util.*;
public class Main {
	public static void main(String args[]) {
		Scanner cin = new Scanner(System.in);
		int a;
		int b;
		while (cin.hasNext()) {
			a = cin.nextInt(); 
			if (a==1){
System.out.printf("0.25\n");
   
}
else if (a==0){
  b=1; 
System.out.printf("0.20\n");}
}
	}	}