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POPolynomial Calculator
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copied!<p>I'm doing a polynomial calculator and i'll need some help as i'll progress with the code.</p> <p>For now I made only the polinom class which i represented it as a linked list with terms and some functions(only read and print the polynomial functions for now).</p> <p>Here's the main program which for now only read a polynomial and prints it:</p> <pre><code>#include "polinom.h" int main() { polinom P1; bool varStatus = false; char var = '\0', readStatus = '\0'; cout << "P1 = "; P1.read(readStatus, var, varStatus); // i don't need readStatus yet as i haven't implemented the reset and quit functions cout << "\n\nP = "; P1.print(var); getch(); return 0; } </code></pre> <p>And the header file polinom.h:</p> <pre><code>#ifndef _polinom_h #define _polinom_h #include <iostream> #include <list> #include <cstdlib> #include <cctype> #include <cstdio> #include <conio.h> using namespace std; class polinom { class term { public: int coef; int pow; term() { coef = 1; pow = 0; } }; list<term> poly; list<term>::iterator i; public: bool printable(char c) { return ( ((int(c) > 42 && int(c) < 123) || isspace(c)) && int(c) != 44 && int(c) != 46 && int(c) != 47 && int(c) != 58 && int(c) != 59 && int(c) != 60 && int(c) != 61 && int(c) != 62 && int(c) != 63 && int(c) != 64 && int(c) != 65 && int(c) != 91 && int(c) != 92 && int(c) != 93 && int(c) != 95 && int(c) != 96 ); } void read(char &readStatus, char &var, bool &varStatus) { term t; // term variable to push it into the list of terms char c, lc, sign; // c = current char, lc = lastchar and sign the '+' or '-' sign before a coefficient int coef, pow; //variables to pass the coef and power to term t bool coefRead = false, powRead = false; //reading status of coef and power while (c != '\r') { //we read characters until carriage return c = getch(); // get the new imputed char if (tolower(c) == 'r' || tolower(c) == 'q') { //if the user inputed r or q we reset the input or quit the program readStatus = c; //pass current char value to readStatus so the program will know what to do next return; //aborting the reading process } else { if (printable(c)) cout << c; //print on screen only the correct characters if (!coefRead && !powRead) //we set term coef to the inputed value { if (isdigit(c)) { if (isdigit(lc)) coef = coef * 10 + int(c); //if the last char was also a digit we multiply the last value of coef by 10 and add current char else { if (sign == '-') coef = -(int(c));//if the current coef has '-' before we set coef to it's negative value else coef = int(c); //this means a new term's coef is read } if (!isdigit(c) && isdigit(lc)) coefRead = true; //if the last char was a digit and we reached the var name we stop reading the coefficient } else if (coefRead && !powRead) //after coefficient is read we get the term's varname and power { if (isdigit(c)) { // just like in the case with coefficient we read the power until the current char is not a digit if (isdigit(lc)) pow = pow * 10 + int(c); else pow = int(c); } else if (isalpha(c) && isdigit(lc) && !varStatus) { //if the last char was a digit and the current not we reached the var name var = c; //also even though the variable is inputed more than once we save it only once varStatus = true; //we mark the var name as read } else { if (isdigit(lc)) powRead = true; } } else { if (c == '+' || c == '-') { // if a sign was inputed it means a new term is coming and we push the current term to the list and reset t.coef = coef; // coefRead and powRead so we can read another term t.pow = pow; poly.push_back(t); sign = c; coefRead = false; powRead = false; } } lc = c; // we save the last character } } } void print(char var) { for ( i=poly.begin() ; i != poly.end(); i++ ) { //going through the entire list to retrieve the terms and print them if (i == poly.end() - 1) { // if we reached the last term if (*(i->pow == 0) //if the last term's power is 0 we print only it's coefficient cout << *(i->coef); else cout << *(i->coef) << var << "^" << *(i->pow); //otherwise we print both } else { if (*(i->coef > 0) //if the coef value is positive cout << *(i->coef) << var << "^" << *(i->pow) << " + "; //we also add the '+' sign else cout << *(i->coef) << var << "^" << *(i->pow) << " - "; // otherwise we add '-' sign } } } }; #endif </code></pre> <p><strong>EDIT</strong></p> <p>All compile errors fixed now thanks to JonH, but the read function is not working as the input characters aren't correctly inserted into the list. I know it may be trivial for you guys, but it would be great if you help me out.</p> <p>Thanks!</p>

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