// "Enter an expression." // "Example: 9 * 5 + 27 * LOG(30) / sin(60) * 5^3 + 778 - 88 + 8843 - 727 - 829" #include #include #include #include #define PI 3.14159265358979323846 using namespace std; string strtolower(string s); string strip_spaces(string s); vector split(string s, string delimiter); int countOccurances(string haystack, string needle); int findLeftPos(string expression, int e); string processExponential(string expression); int findRightPos(string expression, int e); string processArithmetic(string expression); string processFunctions(string s); string processSum(string s); string strtolower(string s) { string str = ""; for(char& c : s) { c = tolower(c); str = str + c; } return str; } string strip_spaces(string s){ while(s.find(" ") != -1){ s.erase(s.find(" "),1); } return s; } vector split(string s, string delimiter){ vector parts; string part; while(s.find(delimiter) != -1){ part = s.substr(0,s.find(delimiter)); s.erase(0,part.size() + delimiter.size()); parts.push_back(part); } parts.push_back(s); return parts; } int countOccurances(string haystack, string needle){ int count = 0; while(haystack.find(needle) != -1){ haystack.erase(haystack.find(needle),needle.size()); count++; } return count; } int findLeftPos(string expression, int e){ e--; while(e){ if (expression.substr(e,1) == "*" || expression.substr(e,1) == "/" || expression.substr(e,1) == "+" || expression.substr(e,1) == "-"){ break; } e--; } return e; } int findRightPos(string expression, int e){ e++; while(e < expression.size()){ if (expression.substr(e,1) == "*" || expression.substr(e,1) == "/" || expression.substr(e,1) == "+" || expression.substr(e,1) == "-"){ break; } e++; } return e; } string processExponential(string expression){ while(expression.find("^") != -1){ int expPos = expression.find("^"); int leftPos = -1, rightPos = -1; int e = expPos; string leftPart, rightPart; leftPos = findLeftPos(expression,e); rightPos = findRightPos(expression,e); if (leftPos == 0){ leftPos--; } leftPart = processArithmetic(processFunctions(expression.substr(leftPos + 1, expPos - leftPos - 1))); rightPart = processArithmetic(processFunctions(expression.substr(expPos + 1, rightPos - expPos - 1))); expression.replace(expression.find(leftPart + "^"), leftPart.size() + rightPart.size(), to_string(pow(stod(leftPart), stod(rightPart)))); } return expression; } string processArithmetic(string expression){ if (expression.find("^") != -1){ expression = processExponential(expression); } vector operations = {"/","*"}; for (int i = 0; i < operations.size();i++){ while(expression.find(operations.at(i)) != -1){ int expPos = expression.find(operations.at(i)); int leftPos = -1, rightPos = -1; int e = expPos; string leftPart, rightPart; leftPos = findLeftPos(expression,e); rightPos = findRightPos(expression,e); if (leftPos == 0){ leftPos = leftPos - 1; } leftPart = processArithmetic(processFunctions(expression.substr(leftPos + 1, expPos - leftPos - 1))); rightPart = processArithmetic(processFunctions(expression.substr(expPos + 1, rightPos - expPos - 1))); if (operations.at(i) == "/"){ expression.replace(expression.find(leftPart + operations.at(i)), leftPart.size() + rightPart.size(), to_string(stod(leftPart)/stod(rightPart))); } else if (operations.at(i) == "*"){ expression.replace(expression.find(leftPart + operations.at(i)), leftPart.size() + rightPart.size(), to_string(stod(leftPart)*stod(rightPart))); } } } return expression; } void removeEmptyStrings(vector &vStr){ vector vStrNew; for (auto &str : vStr) { if (str.size() != 0){ vStrNew.push_back(str); } } vStr = vStrNew; } void reSplit(vector &vStr, string delimiter){ vector vStrNew; for(auto &str : vStr){ if (str.find(delimiter) != -1){ vector splitted = split(str, delimiter); vStrNew.push_back(splitted.at(0)); } else { vStrNew.push_back(str); } } vStr = vStrNew; } string processSum(string s){ if (!(s.substr(0, 1) == "+" || s.substr(0, 1) == "-")){ s = "+" + s; } double positivePart = 0, negativePart = 0; vector positiveSplit = split(s,"+"); removeEmptyStrings(positiveSplit); reSplit(positiveSplit,"-"); vector negativeSplit = split(s, "-"); removeEmptyStrings(negativeSplit); reSplit(negativeSplit, "+"); for (auto& str : positiveSplit){ if (str.length() > 0) { positivePart += stod(str); } } for (auto &str : negativeSplit) { if (str.length() > 0){ negativePart += stod(str); } } return to_string(positivePart - negativePart); } string processFunctions(string s){ vector functions = {"arcsin(","arctan(","arccos(","sin(","tan(","cos(","log(","ln(","sinh(","cosh(","tanh(","asinh(","acosh(","atanh("}; vector strSplit, splitExp; string function; int i, j; string exp, exp2; double val; double expVal; for (i = 0;i < functions.size();i++){ function = functions.at(i); function = function.substr(0,function.size() - 1); if (s.find(functions.at(i)) != -1){ strSplit = split(s,functions.at(i)); for (j = 1; j < strSplit.size();j++){ exp = strSplit.at(j); splitExp = split(exp,")"); exp = splitExp.at(0); exp2 = exp; expVal = stod(exp); if(function == "sin"){ val = sin (expVal * PI / 180.0); } else if(function == "tan"){ val = tan (expVal * PI / 180.0); } else if(function == "cos"){ val = cos (expVal * PI / 180.0); } else if(function == "arctan"){ val = atan (expVal) * 180 / PI; } else if(function == "arcsin"){ val = asin (expVal) * 180 / PI; } else if(function == "arccos"){ val = acos (expVal) * 180 / PI; } else if(function == "log"){ val = log10 (expVal); } else if(function == "ln"){ val = log (expVal); } else if(function == "sinh"){ val = sinh (expVal * PI / 180.0); }else if(function == "cosh"){ val = cosh (expVal * PI / 180.0); }else if(function == "tanh"){ val = tanh (expVal * PI / 180.0); }else if(function == "asinh"){ val = asinh (expVal * PI / 180.0); }else if(function == "acosh"){ val = acosh (expVal * PI / 180.0); }else if(function == "atanh"){ val = atanh (expVal * PI / 180.0); } s.replace(s.find(functions.at(i)), functions.at(i).size() + exp2.size() + 1, to_string(val)); } } } return s; } int main(){ // "Enter an expression." // "Example: 9 * 5 + 27 * LOG(30) / sin(60) * 5^3 + 778 - 88 + 8843 - 727 - 829" string exp; cin>>exp; exp = strip_spaces(exp); if (countOccurances(exp,"(") != countOccurances(exp,")")){ cout << "Syntax error" << endl; return 1; } string a = processSum(processArithmetic(processFunctions(strtolower(exp)))); cout << a << endl; return 0; }

c++ Calculator