Mathematical expressions usually use infix notation in which the operator is in between the operands: (1+...

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Mathematical expressions usually use infix notation in which the operator is in between the operands: (1+ (2 3)). With prefix notation, the operator comes first: (+1(*23)). You are to write a program that evaluates expressions written in prefix notation. The values will be all integers and the only operators you need to handle are +,,, and /, all of which retain their traditional meanings. Note that with prefix notation, we are not limited to just two operands. That is, we can add any number of values: (+1234) evaluates to 10. This also works for and /. (-10 123) is interpreted as 10-1-2-3 and evaluates to 4. Here is the recursive definition of your expressions: expression: integer value or: (operator value_list) value_list: expression or: expression value_list Operator: or-or/or* 3.2. Notes Your program can assume that the input is well-formed. For example, there will be no bad operators, floating point values, unmatched parentheses, or missing arguments. All the tokens in the input will be separated by whitespace (space, tab, or newline) which means that you can use Scanner.getNext() to get each token. Your program is to continue to accept expressions until the user enters "done". Ignore case on this comparison. Your output must include your name. Your solution must be recursive. Turn in only your source file: PrefixEvaluation.java. Make sure your class is not in a package (that is, it is in the default package). Hint: Consider writing a single recursive method int eval(String e) which evaluates e. Ife is an integer (the base case), just return its value. If e isn't an integer, it must be start with a "("(recursive case). Read the operator next, then read, evaluate and store (ArrayList?) expressions until you find the matching ")". Once you have your values (the operands to the operation), perform the required operation and return its result. 3.3. Required Main Class PrefixEvaluation 3.4. Required Input A series of prefix expressions followed by "done". Mathematical expressions usually use infix notation in which the operator is in between the operands: (1+ (2 3)). With prefix notation, the operator comes first: (+1(*23)). You are to write a program that evaluates expressions written in prefix notation. The values will be all integers and the only operators you need to handle are +,,, and /, all of which retain their traditional meanings. Note that with prefix notation, we are not limited to just two operands. That is, we can add any number of values: (+1234) evaluates to 10. This also works for and /. (-10 123) is interpreted as 10-1-2-3 and evaluates to 4. Here is the recursive definition of your expressions: expression: integer value or: (operator value_list) value_list: expression or: expression value_list Operator: or-or/or* 3.2. Notes Your program can assume that the input is well-formed. For example, there will be no bad operators, floating point values, unmatched parentheses, or missing arguments. All the tokens in the input will be separated by whitespace (space, tab, or newline) which means that you can use Scanner.getNext() to get each token. Your program is to continue to accept expressions until the user enters "done". Ignore case on this comparison. Your output must include your name. Your solution must be recursive. Turn in only your source file: PrefixEvaluation.java. Make sure your class is not in a package (that is, it is in the default package). Hint: Consider writing a single recursive method int eval(String e) which evaluates e. Ife is an integer (the base case), just return its value. If e isn't an integer, it must be start with a "("(recursive case). Read the operator next, then read, evaluate and store (ArrayList?) expressions until you find the matching ")". Once you have your values (the operands to the operation), perform the required operation and return its result. 3.3. Required Main Class PrefixEvaluation 3.4. Required Input A series of prefix expressions followed by "done". Page < 6 of 6 - ZOOM + --------- 3.5. Required Output For each expression, evaluate the expression and print the result. You can use the examples below as a set of test cases. Your output should look like the following (input is in GREEN). Prefix Evaluation - Your Name Enter an expression: 3 Evaluates to 3 Enter an expression: ( +12) Evaluates to 3 Enter an expression: ( / 16 3 ) Evaluates to 5 Enter an expression: ( -10 1 2 3 ) Evaluates to 4 Enter an expression: ( / 120 2 3 4 ) Evaluates to 5 Enter an expression: ( + 1 ( -12 10 ) 3 ( / 20 5 ) 5 ( * 23 ) ) Evaluates to 21 Enter an expression: ( + ( ( * ( / 12 4 ) 2 ) ( + 37 ) ) 10 ) Evaluates to 6 Enter an expression: Done Mathematical expressions usually use infix notation in which the operator is in between the operands: (1+ (2 3)). With prefix notation, the operator comes first: (+1(*23)). You are to write a program that evaluates expressions written in prefix notation. The values will be all integers and the only operators you need to handle are +,,, and /, all of which retain their traditional meanings. Note that with prefix notation, we are not limited to just two operands. That is, we can add any number of values: (+1234) evaluates to 10. This also works for and /. (-10 123) is interpreted as 10-1-2-3 and evaluates to 4. Here is the recursive definition of your expressions: expression: integer value or: (operator value_list) value_list: expression or: expression value_list Operator: or-or/or* 3.2. Notes Your program can assume that the input is well-formed. For example, there will be no bad operators, floating point values, unmatched parentheses, or missing arguments. All the tokens in the input will be separated by whitespace (space, tab, or newline) which means that you can use Scanner.getNext() to get each token. Your program is to continue to accept expressions until the user enters "done". Ignore case on this comparison. Your output must include your name. Your solution must be recursive. Turn in only your source file: PrefixEvaluation.java. Make sure your class is not in a package (that is, it is in the default package). Hint: Consider writing a single recursive method int eval(String e) which evaluates e. Ife is an integer (the base case), just return its value. If e isn't an integer, it must be start with a "("(recursive case). Read the operator next, then read, evaluate and store (ArrayList?) expressions until you find the matching ")". Once you have your values (the operands to the operation), perform the required operation and return its result. 3.3. Required Main Class PrefixEvaluation 3.4. Required Input A series of prefix expressions followed by "done". Mathematical expressions usually use infix notation in which the operator is in between the operands: (1+ (2 3)). With prefix notation, the operator comes first: (+1(*23)). You are to write a program that evaluates expressions written in prefix notation. The values will be all integers and the only operators you need to handle are +,,, and /, all of which retain their traditional meanings. Note that with prefix notation, we are not limited to just two operands. That is, we can add any number of values: (+1234) evaluates to 10. This also works for and /. (-10 123) is interpreted as 10-1-2-3 and evaluates to 4. Here is the recursive definition of your expressions: expression: integer value or: (operator value_list) value_list: expression or: expression value_list Operator: or-or/or* 3.2. Notes Your program can assume that the input is well-formed. For example, there will be no bad operators, floating point values, unmatched parentheses, or missing arguments. All the tokens in the input will be separated by whitespace (space, tab, or newline) which means that you can use Scanner.getNext() to get each token. Your program is to continue to accept expressions until the user enters "done". Ignore case on this comparison. Your output must include your name. Your solution must be recursive. Turn in only your source file: PrefixEvaluation.java. Make sure your class is not in a package (that is, it is in the default package). Hint: Consider writing a single recursive method int eval(String e) which evaluates e. Ife is an integer (the base case), just return its value. If e isn't an integer, it must be start with a "("(recursive case). Read the operator next, then read, evaluate and store (ArrayList?) expressions until you find the matching ")". Once you have your values (the operands to the operation), perform the required operation and return its result. 3.3. Required Main Class PrefixEvaluation 3.4. Required Input A series of prefix expressions followed by "done". Page < 6 of 6 - ZOOM + --------- 3.5. Required Output For each expression, evaluate the expression and print the result. You can use the examples below as a set of test cases. Your output should look like the following (input is in GREEN). Prefix Evaluation - Your Name Enter an expression: 3 Evaluates to 3 Enter an expression: ( +12) Evaluates to 3 Enter an expression: ( / 16 3 ) Evaluates to 5 Enter an expression: ( -10 1 2 3 ) Evaluates to 4 Enter an expression: ( / 120 2 3 4 ) Evaluates to 5 Enter an expression: ( + 1 ( -12 10 ) 3 ( / 20 5 ) 5 ( * 23 ) ) Evaluates to 21 Enter an expression: ( + ( ( * ( / 12 4 ) 2 ) ( + 37 ) ) 10 ) Evaluates to 6 Enter an expression: Done