anchor.diff:          
               try{period = Integer.parseInt(request.getParameter("periodo")); 
               taxajrs = Integer.parseInt(request.getParameter("juros")); 
  -            vlprincipal = Integer.parseInt(request.getParameter("valorprincipal"));
  -           
  -        
  +            vlprincipal = Integer.parseInt(request.getParameter("valorprincipal")); 
               }
               catch(Exception e){}
               
  
positive.code:  
         
                 
          double vlprincipal = 0 ; 
          int period = 0 ;
          double taxajrs=0;
          
        
         
  
negative.code:          <br>
              <form>
                  <p>Valor Principal:<input type="text" name="valorprincipal"></p>
                  <p>Período em Meses:<input type="text" name="periodo"><p/>
                  <p>Taxa de Juros em %:<input type="text" name="juros"></p>
                  
                  <input type="submit" value="Enviar">
              </form>
               
           
              <table border="2">
           <tr> <th><h4>Período</h4></th>  <th><h4>Juros</h4></th>  <th><h4>Prestação</h4></th>  <th><h4>Amortização</h4></th>  <th><h4>Saldo devedor</h4></th></tr> 
                      
          
           
              <!-- Repetição das celulas da tabela -->
                      <%for(int i=0; i<= period; i++){%>
                          <% if (i <= 0){ %>
                      <h3><tr>
                        <td><h4> <%= 0 %> </h4></td>
                        <td><h4> <%= 0 %> </h4></td>
                        <td><h4> <%= 0 %>  </h4></td>
                        <td><h4> <%= 0 %></h4></td>
                        <td><h4> <%= saldodev = vlprincipal - saldodev %> </h4></td>
                         <% }else{ %>
             
                        <td><h4> <%=i%> </h4></td>
                        <td><h4> <%= taxajrsaux = ((taxajrs/100)*saldodev) %> </h4></td>
                        <td><h4> <%= parcel = (vlprincipal)/((Math.pow((1+(taxajrs/100)),period)-1)/(Math.pow((1+(taxajrs/100)),period*1))) %>  </h4></td>
                        <td><h4> </h4></td>
                        <td><h4> </h4></td>
                            
                        <% } %>
                      </h3></tr>
                             <%}%>
              </table>
                            
                      
          
          <br>
          <form action="home.jsp">
  