Chemical calculator: Difference between revisions

=={{header|C++}}==

{{trans|C#}}

<lang cpp>#include <iomanip>

#include <iostream>

#include <map>

#include <string>

#include <vector>

std::map<std::string, double> atomicMass = {

{"H", 1.008},

{"He", 4.002602},

{"Li", 6.94},

{"Be", 9.0121831},

{"B", 10.81},

{"C", 12.011},

{"N", 14.007},

{"O", 15.999},

{"F", 18.998403163},

{"Ne", 20.1797},

{"Na", 22.98976928},

{"Mg", 24.305},

{"Al", 26.9815385},

{"Si", 28.085},

{"P", 30.973761998},

{"S", 32.06},

{"Cl", 35.45},

{"Ar", 39.948},

{"K", 39.0983},

{"Ca", 40.078},

{"Sc", 44.955908},

{"Ti", 47.867},

{"V", 50.9415},

{"Cr", 51.9961},

{"Mn", 54.938044},

{"Fe", 55.845},

{"Co", 58.933194},

{"Ni", 58.6934},

{"Cu", 63.546},

{"Zn", 65.38},

{"Ga", 69.723},

{"Ge", 72.630},

{"As", 74.921595},

{"Se", 78.971},

{"Br", 79.904},

{"Kr", 83.798},

{"Rb", 85.4678},

{"Sr", 87.62},

{"Y", 88.90584},

{"Zr", 91.224},

{"Nb", 92.90637},

{"Mo", 95.95},

{"Ru", 101.07},

{"Rh", 102.90550},

{"Pd", 106.42},

{"Ag", 107.8682},

{"Cd", 112.414},

{"In", 114.818},

{"Sn", 118.710},

{"Sb", 121.760},

{"Te", 127.60},

{"I", 126.90447},

{"Xe", 131.293},

{"Cs", 132.90545196},

{"Ba", 137.327},

{"La", 138.90547},

{"Ce", 140.116},

{"Pr", 140.90766},

{"Nd", 144.242},

{"Pm", 145},

{"Sm", 150.36},

{"Eu", 151.964},

{"Gd", 157.25},

{"Tb", 158.92535},

{"Dy", 162.500},

{"Ho", 164.93033},

{"Er", 167.259},

{"Tm", 168.93422},

{"Yb", 173.054},

{"Lu", 174.9668},

{"Hf", 178.49},

{"Ta", 180.94788},

{"W", 183.84},

{"Re", 186.207},

{"Os", 190.23},

{"Ir", 192.217},

{"Pt", 195.084},

{"Au", 196.966569},

{"Hg", 200.592},

{"Tl", 204.38},

{"Pb", 207.2},

{"Bi", 208.98040},

{"Po", 209},

{"At", 210},

{"Rn", 222},

{"Fr", 223},

{"Ra", 226},

{"Ac", 227},

{"Th", 232.0377},

{"Pa", 231.03588},

{"U", 238.02891},

{"Np", 237},

{"Pu", 244},

{"Am", 243},

{"Cm", 247},

{"Bk", 247},

{"Cf", 251},

{"Es", 252},

{"Fm", 257},

{"Uue", 315},

{"Ubn", 299},

};

double evaluate(std::string s) {

s += '[';

double sum = 0.0;

std::string symbol;

std::string number;

for (auto c : s) {

if ('@' <= c && c <= '[') {

// @, A-Z

int n = 1;

if (number != "") {

n = stoi(number);

}

if (symbol != "") {

sum += atomicMass[symbol] * n;

}

if (c == '[') {

break;

}

symbol = c;

number = "";

} else if ('a' <= c && c <= 'z') {

symbol += c;

} else if ('0' <= c && c <= '9') {

number += c;

} else {

std::string msg = "Unexpected symbol ";

msg += c;

msg += " in molecule";

throw std::runtime_error(msg);

}

}

return sum;

}

std::string replaceFirst(const std::string &text, const std::string &search, const std::string &replace) {

auto pos = text.find(search);

if (pos == std::string::npos) {

return text;

}

auto beg = text.substr(0, pos);

auto end = text.substr(pos + search.length());

return beg + replace + end;

}

std::string replaceParens(std::string s) {

char letter = 'a';

while (true) {

auto start = s.find("(");

if (start == std::string::npos) {

break;

}

for (size_t i = start + 1; i < s.length(); i++) {

if (s[i] == ')') {

auto expr = s.substr(start + 1, i - start - 1);

std::string symbol = "@";

symbol += letter;

auto search = s.substr(start, i + 1 - start);

s = replaceFirst(s, search, symbol);

atomicMass[symbol] = evaluate(expr);

letter++;

break;

}

if (s[i] == '(') {

start = i;

continue;

}

}

}

return s;

}

int main() {

std::vector<std::string> molecules = {

"H", "H2", "H2O", "H2O2", "(HO)2", "Na2SO4", "C6H12",

"COOH(C(CH3)2)3CH3", "C6H4O2(OH)4", "C27H46O", "Uue"

};

for (auto molecule : molecules) {

auto mass = evaluate(replaceParens(molecule));

std::cout << std::setw(17) << molecule << " -> " << std::setw(7) << std::fixed << std::setprecision(3) << mass << '\n';

}

return 0;

}</lang>

{{out}}

<pre> H -> 1.008

H2 -> 2.016

H2O -> 18.015

H2O2 -> 34.014

(HO)2 -> 34.014

Na2SO4 -> 142.036

C6H12 -> 84.162

COOH(C(CH3)2)3CH3 -> 186.295

C6H4O2(OH)4 -> 176.124

C27H46O -> 386.664

Uue -> 315.000</pre>