Solving a mathematical equation written in words in Java -

im trying solve equation this: four plus ten divided (fifty-five plus nine)

so response: 4.15625

i know can solve equation of string sentence = "4+10/(55+9)" so:

scriptenginemanager mgr = new scriptenginemanager(); scriptengine engine = mgr.getenginebyname("javascript"); string infix = sentence; try {     system.out.println(engine.eval(infix)); } catch (scriptexception e) {     // todo auto-generated catch block     e.printstacktrace(); } 

but there anyway solve words (nine..plus..divide..) equation. or there way convert words (nine..plus..divide..) string (9...+.../...) , use function shown above solve it?

thanks!

you can go parser library antlr better idea if want full, expressive language , proper error handling.

for quick , dirty solution can write own parser using regular expressions , replacement map:

public class naturallanguagemath {      public static void main(string[] args) {         string sentence = "four plus ten divided (fifty-five plus nine)";         system.out.println(tomath(sentence));     }      // regular expression match our symbols     // special case "divided by" since that's 2 words 1 symbol     static final pattern symbol_pattern = pattern.compile("(divided by|[a-z-]+)", pattern.case_insensitive);      private static string tomath(string sentence) {         // builder build translated string         stringbuilder builder = new stringbuilder();         // end of last matched group         int lastend = 0;         // go through symbols in string         matcher matcher = symbol_pattern.matcher(sentence);         while(matcher.find()) {             // matched symbol             string symbol = matcher.group(0).tolowercase();             // replacement             string replacement = getreplacement(symbol);             // append between previous match , match             builder.append(sentence.substring(lastend, matcher.start()));             // append replacement             builder.append(replacement);             // update end             lastend = matcher.end();         }         // append end of string , return         builder.append(sentence.substring(lastend));         return builder.tostring();     }      // map hold replacement symbols     static final hashmap<string, string> replacement_map = new hashmap<>();     static {         replacement_map.put("four", "4");         replacement_map.put("plus", "+");         replacement_map.put("ten", "10");         replacement_map.put("fifty", "50");         replacement_map.put("five", "5");         replacement_map.put("nine", "9");         replacement_map.put("divided by", "/");     }      private static string getreplacement(string symbol) {         // handle compounds such fifty-five         if(symbol.contains("-")) {             // add each individual symbol , return result             // far perfect since allow compounds such             // fifty-five-nine become 64             int value = 0;             // go through each individual symbol , translate             string[] symbols = symbol.split("-");             for(string s : symbols) {                 if(!replacement_map.containskey(s)) {                     throw new illegalargumentexception("unknown symbol: " + s);                 }                 value += integer.parseint(getreplacement(s));             }             return string.valueof(value);         // straight translation         } else if (replacement_map.containskey(symbol)) {             return replacement_map.get(symbol);         // unknown symbol         } else {             throw new illegalargumentexception("unknown symbol: " + symbol);         }     } } 

output:

4 + 10 / (55 + 9)