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###### 日期：2021-04-04 02:34

In the project, you are asked to implement an calculator which has the following elements

and definitions:

1. Number:

? As we all know, the calculator is to perform calculations over numbers. The

acceptable formats of numbers in this project include:

? Integer (e.g., ?23434, 343545, 0) is a number which is not a fraction. It’s

value’s range is from ?1050 to 1050

.

? Real number (e.g.,?23434 .0001 , 0.4343 , 432343 .912 )isthe number which

includes both rational and irrational numbers .In this project ,we represent and

separate areal number aswhole number part,decimal point (i.e.,.), and decimal

part.Specifically,the whole number part,sign and digitslying to the left ofthe

decimal point,isanInteger anditsvalue’srange isfrom ?1050 to1050;thedecimal

part isformed by the digits lying on the right ofdecimal point,and the number of

digitsisbetween1to50.Forexample,thewhole

number part, and the decimal part of the real number ?23434.0001 are ?23434

and 0001 respectively.

? E-notation form of scientific notation (e.g., 3E3, 3.2E3, 3.2E?3, ?3.2E?

3) is another form to represent Integer and Real number. The form mEn

corresponds to the number m × n

10, for example, 350 (i.e., 3.5 × 102

) can be

written as 3.5E2. Specifically, the m is an Integer or Real number, and its

absolute value remains at least one but less than ten, i.e., 1 ≤ |m| < 10; the n

is an Integer, and its value’s range is from ?49 to 49.

? Hint & Note: (1) as the calculator may compute very large/small numbers,

you may need use arrays to represent numbers. (2) the above mentioned range

of the number is applicable to the input.

2. Basic Operations:

? The basic operations (i.e., addition, subtraction, multiplication, division) follows

the same definition and rules (e.g., the precedence and associativity) of

the C operators. The first four operations has two number operands, annotated

as a and b.

? Addition (+) (e.g., ?3434+0.123, 23.3434+0.123, 3.2E?3+3.2). The general

format of it is a + b (no space among a, + and b).

? Subtraction (?) (e.g., ?3434 ? 0.123, 23.3434 ? 0.123, 3.2E ? 3 ? 3.2). The

general format of it is a ? b (no space among a, ? and b).

? Multiplication (?) (e.g., ?3434 ? 0.123, 23.3434 ? 0.123, 3.2E ? 3 ? 3.2). The

general format of it is a ? b (no space among a, ? and b).

? Division (/) (e.g., ?3434/0.123, 23.3434/0.123, 3.2E ? 3/3.2). The general

format of it is a/b (no space among a, / and b). Note that you do not need to

consider the integer division here, for example, the result of 5/2 is 2.5.

3. Arithmetic Expression.

? An arithmetic expression evaluates to a single arithmetic value (i.e., a number).

It can be combined by the operands, basic operations, and parentheses.

? Basic operations. For example, 15.3??3434+0.123, 23.3434+0.123/2E1, 3.2E?

1+3.2?6.5?2/4.0 are the expressions. For the expression 3.2E ?1+3.2?6.5?

2/4.0, we compute it by the following steps (1) 6.5?2 → 13; (2) 13/4.0 → 3.25;

(3) 3.2E ? 1 + 3.2 → 3.52; (4) 3.52 ? 3.25 → 0.27.

? Parentheses (()). The parentheses also shares the same rules as them in

the C expression. The precedence of parentheses is higher than those of basic

operations. For example, the steps of computing the expression 3.2E ? 1 +

(3.2 ? 6.5) ? 2/4.0 are (1) (3.2 ? 6.5) → ?3.3; (2) ?3.3 ? 2 → ?6.6; (3)

?6.6/4.0 → ?1.65; (4) 3.2E ?1 +?1.65 → ?1.33. An expression may contain

multiple parentheses, and the parentheses can be nested, e.g., (3.2E?1+(3.2?

6.5)) ? 2/4.0 and (3.2E ? 1 + (3.2 ? 6.5)) ? (2/4.0).

The calculator receives a series of arithmetic expressions and outputs the values of those

expressions respectively.

1. Input:

? The first line of the input is the number of the expressions, annotated as N.

And the given N is guaranteed as valid (i.e, positive integer).

? The following N lines are the expressions S = {si}

N

i=1, and each expression

is given per line. There is a non-negative integer pi and a character ci after

each expression si

. Specifically, (1) there is no space in si

; (2) there is a

space between si and pi and a space between pi and ci

; (3) 0 ≤ pi ≤ 50; (4)

ci = {D, E}.

? Sample input:

4

30.2 2 D

30.2 2 E

6/0.0 2 E

3.2E ? 1 + (3.2 ? 6.5) ? 2/4.0 1 D

2. Output:

? The first line of the output is the text of Result:.

? The following N lines contain the values of the corresponding expressions, and

each value is given per line. For the expression si

, the pi

is the precision of the

value of si

, which means that we round to pi decimal places for the value. The

ci = {D, E} is the output format, and D and E correspond to the Real number

and E-notation form of scientific notation forms respectively.

? If the input expression is invalid (e.g., beyond the range of number, division

by zero, etc.), output the text of Invalid. Otherwise, output the value of the

corresponding expression in correct format.

? Sample output corresponding to the sample input:

Result:

30.20

3.020E1

Invalid

?1.3

3