Postfix calculator, written in ANSI C

Minor cleanup

Replaced string parsing with scanf

Removed logic examples for readme

- read-only
- https://git.sr.ht/~rabbits/firth
- read/write
- git@git.sr.ht:~rabbits/firth

A postfix calculator with fractions, written in ANSI C.

```
cc 1th.c -std=c89 -Os -DNDEBUG -g0 -s -Wall -o 1th
```

The supported operations are as follow:

`.`

Print fraction`std`

Standard(default)`mix`

Mixed`dec`

Decimal`hex`

Hexadecimal`bin`

Binary

`clr`

Discards stack`pop`

Discards the top stack item`swp`

Reverses the top two stack items`dup`

Duplicates the top stack item`ovr`

Copies second item to top`rot`

Rotates third item to top

`add`

, or`+`

`sub`

, or`-`

`mul`

, or`*`

`div`

, or`/`

`mod`

, or`%`

`and`

, or`&`

`or`

, or`|`

`xor`

, or`^`

`rol`

, or`<<`

`ror`

, or`>>`

`inv`

Invert numerator and denominator`vid`

Convert fraction to two whole numbers

The following example, will print the result `3&1/6`

.

```
clr 11 4 div 5 12 div add _
```

To get the `floor`

of a fraction.

```
clr 17 4 div dup 1 mod sub .
```

To round a the fraction `-12/8`

.

```
clr 0 12 sub 8 div dup dup 1 mod sub swp dup vid swp pop swp vid mod 2 mul swp div dup 1 mod sub add .
```

- The
**Numerator**is the top of part of a fraction. - The
**Denominator**is the bottom of part of a fraction. - A
**Proper Fraction**has a numerator that is smaller than its denominator and represents a quantity less than the whole. - An
**Improper Fraction**has a numerator larger than its denominator and represents a quantity greater than the whole. **Mixed Numbers**are whole numbers and portions less than 1 added together, like`2 3/4`

.**Like Fractions**are fractions with the same denominators.**Unlike Fractions**are fractions with different denominators.- A
**Reciprocal**is the inverted value of a fraction, like`12/34`

is the reciprocal of`34/12`

.