calculator - Splitting calculations in a stack C++ -


i trying learn c++. have created calculator allows 1 line text input, splits string , performs calculation depending on operator.
syntax 5*2 of course return 10.
next step allow multiple operators in same line i.e. 5*2/4
advise on how might this? imagine looping or push/pop have no idea route work best.

understand there many calculators such reverse polish notation wondered if me 1 in particular. thanks.

#include <iostream> using namespace std;  int main() {      while (true) {         string str;         float eq1;         float eq2;         cout << "request: " << flush;         cin >> str;          if (str.find('/') != string::npos) {             int pos = str.find("/");             string sub1 = str.substr(0, pos);             eq1 = stof(sub1);             string sub2 = str.substr(pos + 1);             eq2 = stof(sub2);             cout << eq1 / eq2 << endl;         }         else if (str.find('*') != string::npos) {             int pos = str.find("*");             string sub1 = str.substr(0, pos);             eq1 = stof(sub1);             string sub2 = str.substr(pos + 1);             eq2 = stof(sub2);             cout << eq1 * eq2 << endl;         }         else if (str.find('-') != string::npos) {             int pos = str.find("-");             string sub1 = str.substr(0, pos);             eq1 = stof(sub1);             string sub2 = str.substr(pos + 1);             eq2 = stof(sub2);             cout << eq1 - eq2 << endl;         }         else if (str.find('+') != string::npos) {             int pos = str.find("+");             string sub1 = str.substr(0, pos);             eq1 = stof(sub1);             string sub2 = str.substr(pos + 1);             eq2 = stof(sub2);             cout << eq1 + eq2 << endl;         }     } }

the general method take string whole , separate operators (*, /, +, -, etc.) operands (the numbers). making 2 stacks , inserting operators 1 stack , operands other. in calculation phase, pop 2 operands , pop 1 operator , calculation. keep doing until both stacks empty. luck!


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