/*********************************************************************
TRUTH TABLE FOR WELL FORMED FORMULA
*********************************************************************/
#include<stdio.h>
#include<math.h>
#include<string.h>
#include<conio.h>
#include<ctype.h>
//Stack to implement the Postfix_Evaluation
int stack2[20];
int top2 = -1;
void push2(int x)
{
stack2[++top2] = x;
}
int pop2()
{
return stack2[top2--];
}
//Function to evalutae the postfix expression
int evluate_postfix(char *postfix,int val[])
{
char *e;
int n1,n2,n3,num;
e = postfix;
while(*e != '\0')
{
if(isalnum(*e))
{
num = val[*e-'A'];
push2(num);
}
else
{
if(*e=='\''){
n1 = pop2();
n3 = !n1;
//push2(n)
}
else{
n1 = pop2();
n2 = pop2();
switch(*e)
{
case '+':
n3 = n1 || n2;
break;
case '.':
n3 = n1 && n2;
break;
}
}
push2(n3);
}
e++;
}
int z = pop2();
return z;
}
int k = 0;
char stack1[100];
int top1 = -1;
void push1(char x)
{
stack1[++top1] = x;
}
char pop1()
{
if(top1 == -1)
return -1;
else
return stack1[top1--];
}
int priority(char x)
{
if(x == '(')
return 0;
if(x == '+')
return 1;
if(x == '.')
return 2;
if(x == '\'')
return 3;
return 0;
}
//Function to convert the infix expression to postfix expression
char* Infix_To_Postfix(char *exp)
{
char *e, x;
e = exp;
static char postfix[50];
while(*e != '\0')
{
if(isalnum(*e)){
postfix[k++] = *e;
//printf("%c ",*e);
}
else if(*e == '('){
//postfix[k++] = push1(*e);
push1(*e);
}
else if(*e == ')')
{
while((x = pop1()) != '(')
postfix[k++] = x;
//printf("%c ", x);
}
else
{
while(priority(stack1[top1]) >= priority(*e)){
postfix[k++] = stack1[top1];
pop1();
//printf("%c ",pop1());
}
push1(*e);
}
e++;
}
while(top1 != -1)
{
// printf("%c ",pop1());
postfix[k++] = stack1[top1];
pop1();
}return postfix;
}
//Function to increment the truth table
int increment(char *var,int val[],int len){
int carry = 1;
for (int i = len - 1; i >= 0; --i) {
if (val[var[i] - 'A'] == 1 && carry == 1) {
val[var[i] - 'A'] = 0;
}
else if (carry == 1) {
val[var[i] - 'A'] = 1;
carry = 0;
}
}
}
//Function for the truth table
void print_truth_table(char *s){
int i,len,k=0;
char var[50] , *postfix;
int val[26],n;
for(i=0;i<26;i++){
val[i] = -1;
}
//for loop for get and store the number of variable's
len = strlen(s);
for(i=0;i<=len;i++){
if(s[i]>='A' && s[i]<='Z' && val[s[i]-'A']==-1){
val[s[i]-'A']=0;
var[k++] = s[i];
}
}
postfix = Infix_To_Postfix(s);
// printf("The postfix is %s",postfix);
n = strlen(var);
printf("\nTRUTH TABLE FOR INPUT BOOLEAN EXPRESSION\n");
for (int i = 0; i <=n; ++i) {
printf("---------------");
}
printf("\n");
for (int i = 0; i < n; ++i) {
printf("| %c ",var[i]);
}
printf("| ");
printf("Result |\n");
for (int i = 0; i<=n; ++i) {
printf("---------------");
}
printf("\n");
for (int i = 0; i < pow(2, n); ++i) {
for (int i = 0; i < n; ++i) {
printf("| %d ",val[var[i]-'A']);
}
printf("| ");
int z = evluate_postfix(postfix, val);
printf(" %d |",z);
printf("\n");
increment(var, val,n);
}
for (int i = 0; i <=n; ++i) {
printf("---------------");
}
printf("\n");
}
//Main function
int main(){
int i = 1;
while(i!=0){
char s[50];
printf("\nPlease following the instruction\n OR = + ||\tAND = . || \tNOT = ' ||\n\n");
printf("Please Enter boolean expression (in UPPERCASE) ::");
scanf("%s",s);
print_truth_table(s);
printf("\nIF YOU WANT ANOTHER BOOLEAN EXPRESSION PRESS ANY INTIGER OTHERWISE ENTER 0 \nyour entered intiger is ::");
scanf("%d",&i);
if(i==0){
break;
}
}
}
