import java.util.ArrayList;
import java.util.Iterator;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
char[] variables = setVariables(in);
int[] minTerms = setMinTerms(in);
String[] binaryMinTerms = decimalToBinary(variables, minTerms);
ArrayList<Group> groups = computeSuccessiveGroups(minTerms, binaryMinTerms);
displayInput(variables, minTerms);
printPIs(groups, variables);
}
private static char[] setVariables(Scanner in) {
System.out.print("Enter the number of variables: ");
int numVariables = in.nextInt();
char[] variables = new char[numVariables];
System.out.print("Enter each variable separated by spaces: ");
for(int i = 0; i < numVariables; i++) {
variables[i] = in.next().charAt(0);
}
return variables;
}
private static int[] setMinTerms(Scanner in) {
System.out.print("Enter the number of min terms: ");
int numMinTerms = in.nextInt();
int[] minTerms = new int[numMinTerms];
System.out.print("Enter each min term separated by spaces: ");
for(int i = 0; i < numMinTerms; i++) {
minTerms[i] = in.nextInt();
}
return minTerms;
}
private static String[] decimalToBinary(char[] variables, int[] minTerms) {
String[] binaryMinTerms = new String[minTerms.length];
for(int i = 0; i < minTerms.length; i++) {
binaryMinTerms[i] = Integer.toBinaryString(minTerms[i]);
if(binaryMinTerms[i].length() < variables.length) {
String zeros = "";
int len = binaryMinTerms[i].length();
while(len < variables.length) {
zeros = zeros.concat("0");
len++;
}
binaryMinTerms[i] = zeros + binaryMinTerms[i];
}
}
return binaryMinTerms;
}
private static void displayInput(char[] variables, int[] minTerms) {
System.out.print("Function: f(");
for(int i = 0; i < variables.length; i++) {
if(i == variables.length-1)
System.out.print(variables[i]);
else
System.out.print(variables[i] + ", ");
}
System.out.print(") = SIGMAm(");
for(int i = 0; i < minTerms.length; i++) {
if(i == minTerms.length-1)
System.out.print(minTerms[i]);
else
System.out.print(minTerms[i] + ", ");
}
System.out.println(")");
}
private static ArrayList<Group> computeSuccessiveGroups(int[] minTerms, String[] binaryMinTerms) {
ArrayList<Group> groups = new ArrayList<Group>();
for(int i = 0; i < minTerms.length; i++)
groups.add(new Group(Integer.toString(minTerms[i]), binaryMinTerms[i]));
int sizeBeforeRemoval = 0, currentSize;
while(sizeBeforeRemoval != groups.size()) {
currentSize = groups.size();
for(int i = 0; i < currentSize; i++) {
for(int j = i+1; j < currentSize; j++) {
if(differences(groups.get(i).binary, groups.get(j).binary) == 1) {
String combinedBin = combineBinary(groups.get(i).binary, groups.get(j).binary);
groups.get(i).grouped = true;
groups.get(j).grouped = true;
if(isUniqueBin(groups, combinedBin)) {
String newTuple = groups.get(i).decimal + "," + groups.get(j).decimal;
groups.add(new Group(newTuple, combinedBin));
}
else break;
}
}
}
sizeBeforeRemoval = groups.size();
Iterator<Group> iter = groups.iterator();
while(iter.hasNext()) {
Group next = iter.next();
if(next.grouped)
iter.remove();
}
}
return groups;
}
private static int differences(String a, String b) {
int diff = 0;
for(int i = 0; i < a.length(); i++)
if(a.charAt(i) != b.charAt(i))
diff++;
return diff;
}
private static String combineBinary(String a, String b) {
String combined = "";
for(int i = 0; i < a.length(); i++) {
if(a.charAt(i) != b.charAt(i))
combined = combined.concat("-");
else
combined = combined.concat(Character.toString(a.charAt(i)));
}
return combined;
}
private static boolean isUniqueBin(ArrayList<Group> groups, String s) {
for(int i = 0; i < groups.size(); i++)
if(groups.get(i).binary.equals(s))
return false;
return true;
}
private static void printPIs(ArrayList<Group> groups, char[] variables) {
System.out.println("Prime Implicants: ");
for(int i = 0; i < groups.size(); i++)
System.out.println(groups.get(i).decimal + " | " + binaryToMinTerm(variables, groups.get(i).binary));
}
private static String binaryToMinTerm(char[] variables, String s) {
String minTerm = "";
for(int i = 0; i < s.length(); i++) {
if(s.charAt(i) != '-') {
if(s.charAt(i) == '0')
minTerm = minTerm.concat(Character.toString(variables[i]) + "'");
else
minTerm = minTerm.concat(Character.toString(variables[i]));
}
}
return minTerm;
}
}