content: import java.util.Scanner;
  
  public class Propositional_Logic_Calculator {
    
    private static String res, p, q, operation;
    private static int initial, prop;
    
    public static void main(String[] args){
      
      /*
        User enters x amount of propostions and selects what [Note:[it's two for now]]
        Propositional Operator they would like. Then the action is performed
        
        1. First input will be prompted
        2. Operation will be prompted
        3. Output will be spit out
      */
      
      Scanner sc = new Scanner(System.in);
      
      
      System.out.println("Enter your two propositions below. ");
      
      System.out.println();
      
      System.out.print("Enter your propostion: "); p = sc.nextLine();
      System.out.print("Enter your propostion: "); q = sc.nextLine();
      
      System.out.println();
      
      System.out.println("What connective would you like to use?");
      System.out.println();
  
      System.out.println("Type {N} for negation, {A} for conjunction, {O} for disjunction, {I} for implication, {B} for bicondtional. Please include {}.");
      
      operation = sc.next();
   
      if(operation.equals("{N}")){
         negation(p, q);
      }
      else if (operation.equals("{A}")){
        conjunction(p,q);
      }
      else if (operation.equals("{O}")){
        disjunction(p,q);
      }
      else if (operation.equals("{I}")){
        implication(p,q);
      }
      else if (operation.equals("{B}")){
        biconditional(p,q);
      }
      else {
        System.out.println("Not a valid input. Try again.");
      }
      
      
    }
    
    public static void negation(String p, String q){
      System.out.println("not " + p + ", not " + q  + ".");
    }
    
    public static void conjunction(String p, String q){
      System.out.println(p + " and " + q + ".");
    }
    
    public static void disjunction(String p, String q){
      System.out.println(p + " or " + q + ".");
    }
    
    public static void implication(String p, String q){
      System.out.println("If " + p + ", then " + q + ".");
    }
    
    public static void biconditional(String p, String q){
      System.out.println(p + " if and only if " + q + ".");
    }
    
  }