Question: I want to write a function `double add_100(double x)`, and I have already written the code for `double add_two_numbers(double a, double b)`. **Note**: Here that the variable `x` is local, and hence I need to implement it in the main() function itself. I found `std::bind` could be of help, but could not get how to implement it. Another possibility I think would be `Lambda expressions` but again I am unable to figure out how to implement it.

Answer: 
Try to specific the right `url-pattern` of servlet here:

```
  <servlet-mapping>
   <servlet-name>Login_Bridge</servlet-name>
   <url-pattern>/Login_Bridge</url-pattern>
  </servlet-mapping>

```

Ok try to change this line:

```
 <form action="Login_Bridge" method="get"><button>submit</button></form>

```

With:

```
  <form action="Login_Bridge" method="get"> 
     <input type="submit" value="Submit"/>
  </form>

```
```
<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Json</display-name>
   <servlet>
    <servlet-name>Login_Bridge</servlet-name>
    <servlet-class>com.ebooks.login.main.Login_Bridge</servlet-class>
  </servlet>

  <servlet-mapping>
    <servlet-name>Login_Bridge</servlet-name>
    <url-pattern>/Login_Bridge</url-pattern>
  </servlet-mapping>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>

</web-app>

```

change your web.xml file with this code and read this[link](https://stackoverflow.com/questions/4140448/difference-between-and-in-servlet-mapping-url-pattern)

and change your jsp with this.

```
<form action="/IN/Login_Bridge1" method="post"> 
     <input type="submit" value="Submit"/>
  </form>

```