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Ruby, 31 bytes ->a{a.map{$*[_1]=1.+$*[_1]||0}} Try this online! $* is a global variable, so calling this lambda multiple times (in a single process) would give wrong result. A 32 bytes vers...

posted 3y ago by radarek‭  ·  edited 2y ago by radarek‭

Answer
#6: Post edited by user avatar radarek‭ · 2022-07-26T11:14:34Z (over 2 years ago)
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a,*c{a.map{c[_1]=1.+c[_1]||0}}
  • ```
  • If array consists of positive integers from a known range (lets say `0...1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so calling this lambda multiple times (in a single process) would give wrong result. A 32 bytes version that does not rely on a global state:
  • ```ruby
  • ->a,*c{a.map{c[_1]=1.+c[_1]||0}}
  • ```
  • If array consists of positive integers from a known range (lets say `0...1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
#5: Post edited by user avatar radarek‭ · 2022-01-26T15:19:12Z (almost 3 years ago)
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a{c=Hash.new 0;a.map{c[_1]+=1}}
  • ```
  • If array consists of positive integers from a known range (lets say `0...1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a,*c{a.map{c[_1]=1.+c[_1]||0}}
  • ```
  • If array consists of positive integers from a known range (lets say `0...1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
#4: Post edited by user avatar radarek‭ · 2022-01-15T10:13:14Z (almost 3 years ago)
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so you can calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a{c=Hash.new 0;a.map{c[_1]+=1}}
  • ```
  • If array consists of positive integers from a known range (lets say `0...1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a{c=Hash.new 0;a.map{c[_1]+=1}}
  • ```
  • If array consists of positive integers from a known range (lets say `0...1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
#3: Post edited by user avatar radarek‭ · 2022-01-15T00:27:31Z (almost 3 years ago)
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so you can calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a{c=Hash.new 0;a.map{c[_1]+=1}}
  • ```
  • If array consists of positive integers from a known range (lets say `0..1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so you can calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a{c=Hash.new 0;a.map{c[_1]+=1}}
  • ```
  • If array consists of positive integers from a known range (lets say `0...1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
#2: Post edited by user avatar radarek‭ · 2022-01-14T23:56:12Z (almost 3 years ago)
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so you can call function only once. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a{c=Hash.new 0;a.map{c[_1]+=1}}
  • ```
  • If array consists of positive integers from a known range (lets say `0..1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
  • # [Ruby](https://www.ruby-lang.org/), 31 bytes
  • ```ruby
  • ->a{a.map{$*[_1]=1.+$*[_1]||0}}
  • ```
  • **[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**
  • `$*` is a global variable, so you can calling this lambda multiple times (in a single process) would give wrong result. A 33 bytes version that does not rely on a global state:
  • ```ruby
  • ->a{c=Hash.new 0;a.map{c[_1]+=1}}
  • ```
  • If array consists of positive integers from a known range (lets say `0..1e3`, then 30 bytes version is:
  • ```ruby
  • ->a{b=[0]*1e3;a.map{b[_1]+=1}}
  • ```
#1: Initial revision by user avatar radarek‭ · 2022-01-14T23:55:12Z (almost 3 years ago)
# [Ruby](https://www.ruby-lang.org/), 31 bytes

```ruby
->a{a.map{$*[_1]=1.+$*[_1]||0}}
```

**[Try this online!](https://ato.pxeger.com/run?1=m72kqDSpcsHiNNuYpaUlaboW-3XtEqsT9XITC6pVtKLjDWNtDfW0IayaGoPaWoiqm6YFCmnR0YY6hjpGYGgIhsY6xrGxCsoKunYK0YZgUSOQmI6JjimIHQvRvGABhAYA)**

`$*` is a global variable, so you can call function only once. A 33 bytes version that does not rely on a global state:

```ruby
->a{c=Hash.new 0;a.map{c[_1]+=1}}
```

If array consists of positive integers from a known range (lets say `0..1e3`, then 30 bytes version is:

```ruby
->a{b=[0]*1e3;a.map{b[_1]+=1}}
```