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  1. /* package whatever; // don't place package name! */
  2.  
  3. import java.util.*;
  4. import java.lang.*;
  5. import java.io.*;
  6.  
  7. /* Name of the class has to be "Main" only if the class is public. */
  8. class Ideone
  9. {
  10.  
  11. 	static String next(Scanner s) {
  12. 		String tok;
  13. 		do {
  14. 			tok = s.next();
  15. 		} while (s.hasNext() && tok.trim().length() == 0);
  16. 		return tok;
  17. 	}
  18.  
  19. 	static void require(Scanner s, String mustBe) {
  20. 		if (!next(s).equals(mustBe)) {
  21. 			throw new RuntimeException("Invalid token.");
  22. 		}
  23. 	}
  24.  
  25. 	static String merge(String delim, List<String> operands) {
  26. 		StringBuilder res = new StringBuilder();
  27. 	    boolean first = true;
  28. 		for (String op : operands) {
  29. 			if (!first) {
  30. 			    res.append(delim);
  31. 			} else {
  32. 				first = false;
  33. 			}
  34. 			res.append(op);
  35. 		}
  36.         return res.toString();
  37. 	}
  38.  
  39. 	static String convertInfix(Scanner s) {
  40. 		String tok = next(s);
  41. 		if (tok.equals("AND") || tok.equals("OR") || tok.equals("NOT") || tok.equals("FUNC")) {
  42. 			require(s, "(");
  43. 			List<String> operands = new ArrayList<>();
  44. 			while (true) {
  45. 				operands.add(convertInfix(s));
  46. 				String delim = next(s);
  47. 				if (delim.equals(")")) {
  48. 					break;
  49. 				}
  50. 			}
  51. 			if (tok.equals("AND")) {
  52. 				return "("+merge("&&", operands)+")";
  53. 			}
  54. 			if (tok.equals("OR")) {
  55. 				return "("+merge("||", operands)+")";
  56. 			}
  57. 			if (tok.equals("NOT")) {
  58. 				return "!("+operands.get(0)+")";
  59. 			}
  60. 			// FUNC
  61. 			return "FUNC("+merge(", ", operands)+")";
  62. 		} else if (tok.equals("(")) {
  63. 			String res = convertInfix(s);
  64. 			require(s, ")");
  65. 			return res;
  66. 		} else {
  67. 			// A <operand> B
  68. 			return tok + next(s) + next(s);
  69. 		}
  70. 	}
  71.  
  72. 	static String convertInfix(String s) {
  73. 	    Scanner scanner = new Scanner(s);
  74. 	    scanner.useDelimiter("\\s|\\b|(?<=[()])");
  75. 	    return convertInfix(scanner);
  76. 	}
  77.  
  78. 	public static void main (String[] args) throws java.lang.Exception
  79. 	{
  80. 		String expr = "AND(OR((NOT(A != null)), OR(FUNC(3<4, 1==1), 1<2, FUNC(5<6, 2<3))), 2<3)";
  81. 		System.out.println(convertInfix(expr));
  82. 	}
  83. }
Success #stdin #stdout 0.14s 321408KB
comments ()
stdin 
Standard input is empty
stdout 
((!(A!=null)||(FUNC(3<4, 1==1)||1<2||FUNC(5<6, 2<3)))&&2<3)
https://ideone.com/dh1RRj
language:
Java (HotSpot 12)
created:
8 years ago
visibility:
public

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