int main() 
{ 
    char exp[] = "a+b*(c^d-e)^(f+g*h)-i";
	printf("\tInfix expression: %s", exp);
    infixToPostfix(exp);
    return 0;
}
Пример #2
0
void Eval::compileExpression (const std::string& e)
{
  // Reduce e to a vector of tokens.
  Lexer l (e);
  l.ambiguity (_ambiguity);
  std::string token;
  Lexer::Type type;
  while (l.token (token, type))
  {
    if (_debug)
      context.debug ("Lexer '" + token + "' " + Lexer::type_name (type));
    _compiled.push_back (std::pair <std::string, Lexer::Type> (token, type));
  }

  // Parse for syntax checking and operator replacement.
  if (_debug)
    context.debug ("FILTER Infix        " + dump (_compiled));
  infixParse (_compiled);
  if (_debug)
    context.debug ("FILTER Infix parsed " + dump (_compiled));

  // Convert infix --> postfix.
  infixToPostfix (_compiled);
  if (_debug)
    context.debug ("FILTER Postfix      " + dump (_compiled));
}
Пример #3
0
int main()
{
    std::string infix_expression;
    int column_width = 16;

    std::cout <<std::left <<std::setw(column_width) <<"infix"
        <<std::left <<std::setw(column_width) <<"prefix"
        <<std::left <<std::setw(column_width) <<"postfix"
        <<std::left <<std::setw(column_width) <<"value" <<"\n\n";

    while (getline(std::cin, infix_expression))
    {
        std::string post_fix_expression;
        std::string pre_fix_expression;
        double post_fix_evaluation;
        
        post_fix_expression = infixToPostfix(infix_expression);
        pre_fix_expression = postfixToPrefix(post_fix_expression);
        post_fix_evaluation = evaluatePostfix(post_fix_expression);
        
        std::string::iterator new_end = std::remove_if(infix_expression.begin(), infix_expression.end(), isspace);
        
        std::cout <<std::left <<std::setw(column_width) <<std::string(infix_expression.begin(), new_end)
            <<std::left <<std::setw(column_width) <<pre_fix_expression
            <<std::left <<std::setw(column_width) <<post_fix_expression
            <<std::left <<std::setw(column_width) <<post_fix_evaluation <<std::endl;
    }

    return 0;
}
Пример #4
0
int main() {
	int choice;
	char infix[50], *postfix;

	do {
		printf("(1) Convert infix to postfix expression and evaluate\n");
		printf("(2) Evaluate postfix expression\n");
		printf("(3) Quit\n");
		printf("Enter selection (1, 2, or 3): ");
		scanf("%d", &choice);
		getchar();  // read and ignore newline
		if (choice == 1) {
			printf("Enter Infix Expression: ");
			fgets(infix, 50, stdin);
			infix[strlen(infix) - 1] = '\0'; // trim off newline character
			postfix = infixToPostfix(infix);
			printf("Postfix: %s\n", postfix);
			printf("Evaluates to: %d\n", evaluatePostfix(postfix));
		} else if (choice == 2) {
			printf("Enter Postfix Expression: ");
			fgets(infix, 50, stdin);
			infix[strlen(infix) - 1] = '\0';
			printf("Evaluates to: %d\n", evaluatePostfix(infix));
		} else if (choice == 3) {
			printf("Bye.\n");
		} else {
			printf("Invalid selection. Try again...\n");
		}
	} while (choice != 3);

	return 0;
}
Пример #5
0
void Eval::evaluateInfixExpression (const std::string& e, Variant& v) const
{
  // Reduce e to a vector of tokens.
  Lexer l (e);
  l.ambiguity (_ambiguity);
  std::vector <std::pair <std::string, Lexer::Type> > tokens;
  std::string token;
  Lexer::Type type;
  while (l.token (token, type))
    tokens.push_back (std::pair <std::string, Lexer::Type> (token, type));

  // Parse for syntax checking and operator replacement.
  if (_debug)
    context.debug ("FILTER Infix        " + dump (tokens));
  infixParse (tokens);
  if (_debug)
    context.debug ("FILTER Infix parsed " + dump (tokens));

  // Convert infix --> postfix.
  infixToPostfix (tokens);
  if (_debug)
    context.debug ("FILTER Postfix      " + dump (tokens));

  // Call the postfix evaluator.
  evaluatePostfixStack (tokens, v);
}
Пример #6
0
void main()
{
	int i,j,t;
	struct stack s;
	char post[20],infix[20];
	init(&s);
	push(&s,'5');
	push(&s,'2');
	i=pop(&s);
	j=peep(&s);
	if(s.top!=-1)
	{
		printf("Popped element = %d\n ",i);
		printf("Top element = %d\n ",j);
	}
	printf("Enter the infix expression:\n");
	scanf("%s",infix);
	infixToPostfix(infix,post);
	printf("Postfix statement:\n");
	printf("%s",post);
	/*printf("Enter postfix expression:\n ");
	scanf("%s",post);*/
	t=evaluate(post);
	printf("\nThe result is %d ",t);

}
Пример #7
0
 /**
  * @param expression: a vector of strings;
  * @return: an integer
  */
 int evaluateExpression(vector<string> &expression) {
     if (expression.empty()) {
         return 0;
     }
     vector<string> postfix;
     infixToPostfix(expression, postfix);
     return evaluatePostfixExpression(postfix);
 }
/**
 * Calculates the line and stores the result to destination variable.
 * While doing operations, prints intermediate step information for stacks
 * and postfix expressions.
 * @param codeLine The code line which will be calculated.
 */
void calculateLine(struct code_line *codeLine) {
	printf("----> Arithmetic Expression: %s\n", codeLine->lineContentInfix);
	printf("--> Infix-Postfix Conversion\n");
	infixToPostfix(codeLine);
	printf("--> Parsing Postfix Expression\n");
	parsePostfixExpression(codeLine, codeLine->lineContentInfix[0]);
	printf("----> Operations completed for this arithmetic expression.\n\n\n");
}
Пример #9
0
int main (int argc, char* argv[])
{
	stack myStack;
	stack evalStack;
	createStack(myStack);
	createStack(evalStack);

	printf("Please enter an infix expression");
	scanInfix();
	infixToPostfix(myStack);
	printf("%d", evaluate(evalStack));
}
Пример #10
0
//testing for the asm functions
int main()
{
	String exp = "( ( AX + ( BY * C ) ) / ( D4 - E ) )";
	std::cout << "Infix: \n" << exp << std::endl;
	std::cout << "Postfix: \n" << infixToPostfix(exp) << std::endl;
	
	exp = " ( ( ( A + B ) + ( C + D ) ) + ( E + F ) )";
	std::cout << "Infix: \n" << exp << std::endl;
	std::cout << "Postfix: \n" << infixToPostfix(exp) << std::endl;
	
	exp = "( A + B )";
	std::cout << "Infix: \n" << exp << std::endl;
	std::cout << "Postfix: \n" << infixToPostfix(exp) << std::endl;
	
	exp = "( A + ( B + C ) )";
	std::cout << "Infix: \n" << exp << std::endl;
	std::cout << "Postfix: \n" << infixToPostfix(exp) << std::endl;
	
	exp ="( ( H * ( ( ( ( A + ( ( B + C ) * D ) ) * F ) * G ) * E ) ) + J )";
	std::cout << "Infix: \n" << exp << std::endl;
	std::cout << "Postfix: \n" << infixToPostfix(exp) << std::endl;
}
Пример #11
0
int main() {
    char expr[MAX]; // expressao infixa
    char post[MAX]; // expressao posfixa
    Pilha p;
    int i;
 
    while (scanf("%s", expr) != EOF) {
        inicializaPilha(&p);
        infixToPostfix(expr, &p, post);
        printf("%s\n", post);
    } // fim while
     
    return 0;
}
Пример #12
0
void Eval::compileExpression (
  const std::vector <std::pair <std::string, Lexer::Type>>& precompiled)
{
  _compiled = precompiled;

  // Parse for syntax checking and operator replacement.
  if (_debug)
    context.debug ("FILTER Infix        " + dump (_compiled));
  infixParse (_compiled);
  if (_debug)
    context.debug ("FILTER Infix parsed " + dump (_compiled));

  // Convert infix --> postfix.
  infixToPostfix (_compiled);
  if (_debug)
    context.debug ("FILTER Postfix      " + dump (_compiled));
}
Пример #13
0
int main()
{
	char exp[20];
	printf("enter the expression you want to check\n");
	scanf("%s",exp);
	
	if(expression(exp)==0)			//This condition will check whether equation is valid w.r.t. brackets or not
	{
		printf("Congratulation, Now hopefully result will be 100% correct\n");
	}
	else
		printf("Sorry man, your entered equation is not valid,Now there are uncertain chances for result to be correct unless you didn't use brackets in your eqaution\n");
	
	printf("PostFix form of your Infix Equation is:\n");
	infixToPostfix(exp);
	printf("Thanks for using Program\nHit Any key to quiet\n");
	getch();
	printf("\n");
	return 0;
}
int main(){
	double f;
	node*root;
	double a;
	char infix[max], postfix[max],temp;
	printf("Enter f(x) operator: ");
	scanf("%s",infix);
	printf("Enter x value: ");
	scanf("%lf",&f);
	infixToPostfix(infix,postfix);
	printf("in Reverse Polish notation: ");
	puts(postfix);
	printf("The result: %0.1lf\n",calculator(postfix,f));
	root=createTree(postfix);
	printf("print Tree: ");
	printTree(root);
	printf("\n");
	printf("The result is using Binary Expression: ");
	printf("%0.1lf\n",countTree(root,f));
}
Пример #15
0
int main(int argv, char *argc[])
{
	char *expression = "  (1 * 2 + 5 )+2 + (1*5+5)+ 3";
	char *p;
	//if (argv != 2) {
	//	puts("Usage: a.exe {algorith expression(must valid)}");
	//	return 1;
	//}

	p = infixToPostfix(expression);
	printf("The infix expression is: %s\n", expression);
	puts("+++++++++++++++++++++++++++++++++++++++++++++++");
	printf("The Postfix expression is: %s\n", p);
	if (strchr(expression, '='))
		printf("%s %d\n", expression, processPostfix(p));
	else
		printf("%s =  %d\n", expression, processPostfix(p));

	if (p != NULL)
		free(p);

	return 0;
}
Пример #16
0
//read in valid infix from file and
//convert to postfix
int main()
{
	std::ifstream in;
	in.open("data3-1.txt");
	std::ofstream out;
	out.open("data.txt");
	while(!in.eof())
	{
		String line;
		line.resize(64);
		getLine(in,line);
		//The last time through, it is not EOF, so it stores,
		//a blank string
		if (!in.eof())
		{
			//Don't need the last semicolon and whitespace
			String exp = line.substr(0,line.length()-3);
			out <<"Infix: " << exp << std::endl;
			out <<"Postfix: " << infixToPostfix(exp) << std::endl;
			out << "\n";
		}
	}
	std::cout << "Writing output to data.txt.\n";
}
Пример #17
0
// Driver program to test above functions
int main()
{
    char exp[] = "a+b*(c^d-e)^(f+g*h)-i";
    infixToPostfix(exp);
    return 0;
}
Пример #18
0
int calculator(const string &s) {
	
	return evaluatePostfix(infixToPostfix(s));
}
Пример #19
0
	double Calculator::evaluatePostfix(const char * postfix)
	{
		// TODO: uses the stack to evaluate an input string in postfix notation. 
		// If a divide-by-zero error occurs, throw a custom exception and stop.
		postfix  = infixToPostfix(postfix);
		Stack<double> stackOfDoubles;
		for (unsigned int i = 0; i < strlen(postfix); i++) // Unsigned int to avoid mismatch
		{
			char token = postfix[i];
			if (isdigit(token))
			{
				double operand = 0;
				double convert = 0;
				int countHowManyDecPlaces = 0;
				bool isDecimal = false; // FLAG 
				while (i < strlen(postfix) && (isdigit(postfix[i]) || postfix[i] == '.'))
				{
					// if it's a decimal
					if (postfix[i] == '.')
					{
						i++;
						isDecimal = true;
						continue;
					}
					else
					{
						operand *= 10;
						convert = postfix[i] - '0';
						operand = operand + convert;
						i++;
						if (isDecimal)
						{
							countHowManyDecPlaces++;
						}
					}

				}
				if (countHowManyDecPlaces != 0) // Handling of decimal inputs
				{
					// 1 decimal place
					if (countHowManyDecPlaces == 1)
						operand = operand / 10;
					// 2 decimal places
					if (countHowManyDecPlaces == 2)
						operand = operand / 100;
					// 3 decimal places
					if (countHowManyDecPlaces == 3)
						operand = operand / 1000;
					// 4 decimal places
					if (countHowManyDecPlaces == 4)
						operand = operand / 10000;
					// 5 decimal places
					if (countHowManyDecPlaces == 5)
						operand = operand / 100000;
				}
				i--; // Decrement i inorder to stay return back to track
				stackOfDoubles.push(operand);
			}
			else if (isOperator(token))
			{
				double operand2 = stackOfDoubles.top(); stackOfDoubles.pop(); // Get two operands to prepare for calculator functions
				double operand1 = stackOfDoubles.top(); stackOfDoubles.pop();
				if (operand2 == 0 && (postfix[i] == '/' || postfix[i] == '%'))
				{
					throw DivideByZero();
					return 0;
				}
				if (token == '+') // Perform the operation: operand1 chr operand2
					stackOfDoubles.push(operand1 + operand2);
				if (token == '-') // Perform the operation: operand1 chr operand2
					stackOfDoubles.push(operand1 - operand2);
				if (token == '*') // Perform the operation: operand1 chr operand2
					stackOfDoubles.push(operand1 * operand2);
				if (token == '/') // Perform the operation: operand1 chr operand2
					stackOfDoubles.push(operand1 / operand2);
			}
		}
		double answer;
		answer = stackOfDoubles.top();
		return answer;
	}
Пример #20
0
command_stream_t
make_command_stream (int (*get_next_byte) (void *),
		     void *get_next_byte_argument)
{
  /* FIXME: Replace this with your implementation.  You may need to
     add auxiliary functions and otherwise modify the source code.
     You can also use external functions defined in the GNU C Library.  */
//  error (1, 0, "command reading not yet implemented");
//  return 0;
	
	//get all input chars to buf	
	char* buf = malloc(65536);
	int size = 65536;
	int end_buf = 0;
	int i;
	int val; 
	for (; (val = get_next_byte(get_next_byte_argument)) != EOF; )
	{
		char value = (char) val;	
		if (end_buf >= size)
		{
			char* t_buf = malloc(size *= 2);
			copy(buf, t_buf, size);
			free(buf);
			buf = t_buf;
		}
		buf[end_buf++] = value;
	}
	buf[end_buf++] = ' ';
	
	//handle errors
	if (!basicSyntax(buf))
		error(1, 0, "basic syntax error!");
	
	//tokenize buffer
	tokentype t = NULL_TOKEN;
	char* tokchars = malloc(128);
	int cwp = 0; //current word pointer
	bool commenting; //true or false: are we commenting?
	token* start, *end; //represents linked list of tokens
	token** andstart 	= &start;
	token** andend 		= &end;
	start = end = NULL;

	for (i = 0; i < end_buf;)
	{
		char c = buf[i];
		if (c == '#')
		{
			if (t != NULL_TOKEN)
				addToken_make(&andstart, &andend, t, tokchars, cwp, 0);
			t = NULL_TOKEN;
			free(tokchars);
			tokchars = malloc(128);
			cwp = 0;
			commenting = 1;
			i++;
		}
		else if (c == '\n' && commenting)
		{
			commenting = 0;
			i++;
		}
		else if (commenting)
		{
			i++;
			continue;
		}
		else if (c == '\r')
			continue;
		else if (c == '&')
		{
			if (t != NULL_TOKEN)
				addToken_make(&andstart, &andend, t, tokchars, cwp, 0);
			t = NULL_TOKEN;
			token* andtoken = malloc(sizeof(token));
			andtoken->t = AND_TOKEN;
			andtoken->sub = cur_shellnum;
			addToken(&start, &end, andtoken);
			t = NULL_TOKEN;
			i += 2;
			free(tokchars);
			tokchars = malloc(128);
			cwp = 0;
		}
		else if (c == '|')
		{
			if (t != NULL_TOKEN)
				addToken_make(&andstart, &andend, t, tokchars, cwp, 0);
			t = NULL_TOKEN;
			if (buf[i+1] == '|')
			{
				token* ortoken = malloc(sizeof(token));
				ortoken->t = OR_TOKEN;
				ortoken->sub = cur_shellnum;
				addToken(&start, &end, ortoken);
				t = NULL_TOKEN;
				i += 2;
			}
			else
			{
				token* pipetoken = malloc(sizeof(token));
				pipetoken->t = PIPE_TOKEN;
				pipetoken->sub = cur_shellnum;
				addToken(&start, &end, pipetoken);
				t = NULL_TOKEN;
				i += 1;
			}
			free(tokchars);
			tokchars = malloc(128);
			cwp = 0;
		}		
		else if (c == '(' || c == ')' || c == '<' || c == '>' || c == ';' || c == '\n')
		{
			if (t != NULL_TOKEN)
				addToken_make(&andstart, &andend, t, tokchars, cwp, 0);
			t = NULL_TOKEN;
			addToken_make(&andstart, &andend, tokentypeOf(c), 0, 0, (c == '(' || c == ')'));
			free(tokchars);
			tokchars = malloc(128);
			cwp = 0;
			i++;
		}
		else if (c == ' ' || c == '\t' || !c)
		{
			if (t == WORD_TOKEN)
				tokchars[cwp++] = c;
			else
			{
				free(tokchars);
				tokchars = malloc(128);
				cwp = 0;
				t = NULL_TOKEN;
			}
			i++;
		}
		else if (c == '!' || c == '%' || c == '+' || c == ',' || c == '-' || c == '.' || c == '/' || c == ':' || c == '@' || c == '^' || c == '_' || ('A' <= c && c <= 'Z') || ('a' <= c && c <= 'z') || ('0' <= c && c <= '9'))
		{
			t = WORD_TOKEN;
			tokchars[cwp++] = c;
			i++;
		}
		else
		{
			int xx = 0;
			error (1, 0, "unrecognized character");
		}
	}
	if (t != NULL_TOKEN)
		addToken_make(&andstart, &andend, t, tokchars, cwp, 0);
	
	//clean token stream first
	token* clean;
	token** andclean = &clean;
	for (clean = start; clean; clean = clean->next) //start by removing adjacent newlines and checking syntax of semicolon, pipe, and, and or
		if (clean->t == NEWLINE_TOKEN)
			while (clean->next && clean->next->t == NEWLINE_TOKEN)
			{	
				clean->next = clean->next->next;
				if (clean->next) clean->next->prev = clean;
			}
		else if (clean->t == SEMICOLON_TOKEN || clean->t == PIPE_TOKEN || clean->t == AND_TOKEN || clean->t == OR_TOKEN)
		{
			if (!clean->prev || clean->prev->t == NEWLINE_TOKEN)
				error (1, 0, "illegal semicolon or operator syntax");
		}
	for (clean = start; clean; clean = clean->next) //then check operator syntax once more
		if (clean->t == AND_TOKEN || clean->t == OR_TOKEN || clean->t == PIPE_TOKEN)
		{
			if (!clean->next || clean->next->t == SEMICOLON_TOKEN || !clean->prev || clean->prev->t == SEMICOLON_TOKEN)
				error (1, 0, "illegal operator syntax");
			if (clean->next->t == NEWLINE_TOKEN)
			{
				token* temp = clean->next;
				for (; temp && temp->t == NEWLINE_TOKEN; temp = temp->next);
				if (!temp || temp->t == SEMICOLON_TOKEN)
					error (1, 0, "illegal operator syntax");
			}
		}
		else if (clean->t == LESS_TOKEN || clean->t == GREATER_TOKEN)
			if (!clean->prev || !clean->next || clean->prev->t != WORD_TOKEN || clean->next->t != WORD_TOKEN)
				error(1, 0, "bad redirection!");
			
	for (clean = start; clean; clean = clean->next) //then get rid of all newlines
	{
		if (clean->t == NEWLINE_TOKEN)
		{
			if ((clean->prev != NULL && clean->prev->t != WORD_TOKEN && clean->prev->t != RIGHT_PAREN_TOKEN) || (clean->next != NULL && clean->next->t != WORD_TOKEN && clean->next->t != LEFT_PAREN_TOKEN)) //function as whitespace
			{
				token* p = clean->prev;
				token* n = clean->next;
				p->next = n;
				if (n) n->prev = p;
				continue;
			}
			else //function as semicolon
				clean->t = SEMICOLON_TOKEN;
		}
		if (clean->t == SEMICOLON_TOKEN)
			while (clean->next && clean->next->t == SEMICOLON_TOKEN)
			{	
				clean->next = clean->next->next;
				if (clean->next) clean->next->prev = clean;
			}
	}
			
	if (start && start->t == SEMICOLON_TOKEN)
	{
		start = start->next;
		start->prev = 0;
	}
	
	
	//change token stream from infix to postfix
	token* finalTokenStream = infixToPostfix(start);
	
	command_stream* strm = evaluatePostfix(finalTokenStream);
	
	return strm;
}