Creating a program that converts infix to postfix when reading from an input file (until it hits a '.')and outputting to a file. It is reading in my input well except that it keeps throwing a ) after each input read in. Also it is not outputting my postfix expressions correctly, it seems to be adding them together and not even converting them correctly. Can you see the issue the code, I imagine it is the expression.cpp file during the convertoPostFix function.

My input file:

A+B -C; A + C ;

x*(y+z)-(w+t); A+B*(C+D)-E/F+G+H;

A*B.

Garbage here.

My output.txt results

Infix: A+B-C;) Postfix: (A+B-C;) Infix: A+C;) Postfix: (A+B-C;)(A+C;) Infix: x*(y+z)-(w+t);) Postfix: (A+B-C;)(A+C;)(x(*y+z)(-w+t);) Infix: A+B*(C+D)-E/F+G+H;) Postfix: (A+B-C;)(A+C;)(x(*y+z)(-w+t);)(A+B(*C+D)-E/F+G+H;) Infix: A*B.) Postfix: (A+B-C;)(A+C;)(x(*y+z)(-w+t);)(A+B(*C+D)-E/F+G+H;)(A*B.)

EXPRESSION.H:

#ifndef EXPRESSION__H #define EXPRESSION__H #include #include #include #include #include #include #include #include using namespace std;

class expression { public: bool last; expression(); friend std::istream& operator>>(std::istream&, expression&); friend std::ostream& operator<<(std::ostream&, expression&); void convertToPostFix();

private: std::string ifix, pfix; //convert here move bool const precedence(char, char); };

#endif

EXPRESSION.CPP:

#include #include"expression.h" #include #include #include

using namespace std;

expression::expression() {

stack stack; stack.push('('); ifix.push_back(')');

for (size_t i = 0; i < ifix.size(); ++i) {

if (isdigit(ifix[i]) || isspace(ifix[i])) { pfix.push_back(ifix[i]); }

else if (ifix[i] == '(') { stack.push(ifix[i]); }

else if ((ifix[i])) { char operator1 = ifix[i]; if ((stack.top())) { while (!stack.empty() && precedence(operator1, stack.top())) { pfix.push_back(stack.top()); stack.pop(); } } stack.push(operator1); } else if (ifix[i] == ')') { while (stack.top() != '(') { pfix.push_back(stack.top()); stack.pop(); } stack.pop(); } }

while (!stack.empty()) { pfix.push_back(stack.top()); stack.pop(); } }

std::istream& operator>>(std::istream& in, expression& exp){ char sym; exp.ifix = ""; do { in >> sym; exp.ifix += sym; } while (sym != '.' && sym != ';'); if (sym == '.') exp.last = true; exp.convertToPostFix(); return in; }

std::ostream& operator<<(std::ostream& out, expression& exp) { out << "Infix: " << exp.ifix << std::endl; out << "Postfix: " << exp.pfix << std::endl; return out; }

in2post.cpp: (where im reading in/out)

#include "expression.h" //#include "stack.h" //#include "queue.h" #include //use these two until queue and stack are done #include #include #include #include #include

using namespace std;

int main(){ ifstream fin; ofstream fout; expression exp; queue q; fin.open("input.txt"); fout.open("output.txt");

while (!exp.last) {

fin >> exp; q.push(exp); } fin.close(); while (!q.empty()) { exp = q.front(); fout << exp; q.pop(); } fout.close(); return 0; }