Algorithm Sedgewick Fourth Edition-1th Chapter 141 using a stack to convert a predecessor expression to a post-expression and calculate a value

1.

1 /*************************************************************************2 * Exercise 1.3.103  *  4 *% java infixtopostfix5 * (1 + ((2 + 3) * (4 * 5)))6 * 1 2 3 + 4 5 * * +7  *  8 *% java infixtopostfix9 * (sqrt (1 + 2))Ten * 1 2 + sqrt One  *   A  *************************************************************************/ -  -  Public classInfixtopostfix the { -      Public Static voidMain (string[] args) -     { -stack<string> Ops =NewStack<string>(); +Stack<string> Vals =NewStack<string>(); -  +          while(!stdin.isempty ()) A         { atString s =stdin.readstring (); -              -             if(S.equals ("("))               ; -             Else if(S.equals ("+") | | -S.equals ("-") | | -S.equals ("*") | | inS.equals ("/") | | -S.equals ("sqrt") ) Ops.push (s); to             Else if(S.equals (")")) +             { -String op =Ops.pop (); theString v =Vals.pop (); *                  $                 if(Op.equals ("+") | |Panax NotoginsengOp.equals ("-") | | -Op.equals ("*") | | theOp.equals ("/")) +v = String.Format ("%s%s%s", Vals.pop (), V, op); A                 Else if(Op.equals ("sqrt")) thev = String.Format ("%s%s", V, op); +                  - Vals.push (v); $             } $             ElseVals.push (s); -         } -          the stdout.println (Vals.pop ()); -     }Wuyi}

2.

1 /*************************************************************************2 * Exercise 1.3.113  *  4 *% java evaluatepostfix5 * 1 2 3 + 4 5 * * +6 * 101.07  *  8 *% java evaluatepostfix9 * 1 5 sqrt + 2.0/Ten * 1.618033988749895 One  *   A *% java evaluatepostfix - * 9-105 7/* - * 45.0 the  *   - *% java infixtopostfix | java evaluatepostfix - * (1 + ((2 + 3) * (4 * 5))) - * 101.0 +  *   - *% java infixtopostfix | java evaluatepostfix + * ((1 + sqrt (5))/2.0) A * 1.618033988749895 at  *   -  *************************************************************************/ -  -  Public classEvaluatepostfix - { -      Public Static voidMain (string[] args) in     { -Stack<double> Vals =NewStack<double>(); to  +          while(!stdin.isempty ()) -         { theString s =stdin.readstring (); *              $             if(S.equals (") | |Panax NotoginsengS.equals (")")) ; -             Else if(S.equals ("+") | | theS.equals ("-") | | +S.equals ("*") | | AS.equals ("/") | | theS.equals ("sqrt")) +             { -                 Doublev =Vals.pop (); $                  $                 if(S.equals ("+")) v = vals.pop () +v; -                 Else if(S.equals ("-")) v = vals.pop ()-v; -                 Else if(S.equals ("*")) v = vals.pop () *v; the                 Else if(S.equals ("/")) v = vals.pop ()/v; -                 Else if(S.equals ("sqrt")) v =math.sqrt (v);Wuyi                  the Vals.push (v);  -             } Wu             Else - Vals.push (double.parsedouble (s)); About         } $          - stdout.println (Vals.pop ()); -     } -}

Algorithm Sedgewick Fourth Edition-1th Chapter 141 using a stack to convert a predecessor expression to a post-expression and calculate a value