什么是最好的编程语言？(怎样才能爱上编程呢？)

• Assmbly：机器语言

• C：形式化语言

• Javascript：网编编程语言

• Scheme：与C和Javascript相比，更轻巧，嵌入性更好，是极其灵活的编程语言

合适的语言

Ada

  function Best_Shuffle(S: String) return String is      T: String(S'Range) := S;      Tmp: Character;    begin      for I in S'Range loop        for J in S'Range loop          if I /= J and S(I) /= T(J) and S(J) /= T(I) then            Tmp  := T(I);            T(I) := T(J);            T(J) := Tmp;          end if;        end loop;      end loop;      return T;    end Best_Shuffle;

Bourne (Again) Shell

   #!/usr/bin/env sh     l="1"     while [ "$l" -le 5 ]       do       m="1"       while [ "$m" -le "$l" ]         do         printf "*"         m=`expr "$m" + 1`       done       echo       l=`expr "$l" + 1`     done

C

  int next_pidmap(struct pid_namespace *pid_ns, unsigned int last)    {        int offset;        struct pidmap *map, *end;        if (last >= PID_MAX_LIMIT)            return -1;        offset = (last + 1) & BITS_PER_PAGE_MASK;       map = &pid_ns->pidmap[(last + 1)/BITS_PER_PAGE];       end = &pid_ns->pidmap[PIDMAP_ENTRIES];       for (; map < end; map++, offset = 0) {           if (unlikely(!map->page))               continue;           offset = find_next_bit((map)->page, BITS_PER_PAGE, offset);           if (offset < BITS_PER_PAGE)               return mk_pid(pid_ns, map, offset);       }       return -1;    }

C++

 #include    #include    #include    int main( int argc , char** argv )   {       int linecount = 0;       std::string line;       std::ifstream infile( argv[ 1 ] );       if( infile )       {           while( getline( infile , line ) )           {               std::cout << linecount << ": " << line << '\n';               linecount++;           }       }       infile.close();       return 0;   }

  namespace rosettacode    {      template class queue      {      public:        queue();        ~queue();        void push(T const& t);        T pop();        bool empty();      private:        void drop();        struct node;        node* head;        node* tail;      };      template struct queue::node      {        T data;        node* next;        node(T const& t): data(t), next(0) {}      };      template       queue::queue():        head(0)      {      }      template       inline void queue::drop()      {        node* n = head;        head = head->next;        delete n;      }      template       queue::~queue()      {        while (!empty())          drop();      }      template       void queue::push(T const& t)      {        node*& next = head? tail->next : head;        next = new node(t);        tail = next;      }      template       T queue::pop()      {        T tmp = head->data;        drop();        return tmp;      }      template       bool queue::empty()      {        return head == 0;      }    }

C#

 using System;   using System.Collections.Generic;   using System.IO;   using System.Linq;   class Program   {       static SortedDictionary GetFrequencies(IEnumerable items)       {           var dictionary = new SortedDictionary();           foreach (var item in items)           {               if (dictionary.ContainsKey(item))               {                   dictionary[item]++;               }               else               {                   dictionary[item] = 1;               }           }           return dictionary;       }       static void Main(string[] arguments)       {           var file = arguments.FirstOrDefault();           if (File.Exists(file))           {               var text = File.ReadAllText(file);               foreach (var entry in GetFrequencies(text))               {                   Console.WriteLine("{0}: {1}", entry.Key, entry.Value);               }           }       }   }

Objective-C

  char bytes[] = "some data";    NSString *string = [[NSString alloc] initWithBytes:bytes length:9 encoding:NSASCIIStringEncoding];

   #import     typedef NSArray *(^SOfN)(id);    SOfN s_of_n_creator(int n) {      NSMutableArray *sample = [[NSMutableArray alloc] initWithCapacity:n];      __block int i = 0;      return ^(id item) {        i++;        if (i <= n) {          [sample addObject:item];        } else if (rand() % i < n) {          sample[rand() % n] = item;        }        return sample;      };    }    int main(int argc, const char *argv[]) {      @autoreleasepool {        NSCountedSet *bin = [[NSCountedSet alloc] init];        for (int trial = 0; trial < 100000; trial++) {          SOfN s_of_n = s_of_n_creator(3);          NSArray *sample;          for (int i = 0; i < 10; i++) {            sample = s_of_n(@(i));          }          [bin addObjectsFromArray:sample];        }        NSLog(@"%@", bin);      }      return 0;    } 

Clojure

  (defn divides? [k n] (= (rem n k) 0))    (defn prime? [n]      (if (< n 2)        false        (empty? (filter #(divides? % n) (take-while #(<= (* % %) n) (range 2 n))))))   Lisp形式的队列的定义代码：    (defn make-queue []      (atom []))    (defn enqueue [q x]      (swap! q conj x))    (defn dequeue [q]      (if (seq @q)        (let [x (first @q)]          (swap! q subvec 1)          x)        (throw (IllegalStateException. "Can't pop an empty queue."))))    (defn queue-empty? [q]      (empty? @q))

D

  uint grayEncode(in uint n) pure nothrow {        return n ^ (n >> 1);    }    uint grayDecode(uint n) pure nothrow {        auto p = n;        while (n >>= 1)            p ^= n;        return p;    }    void main() {        import std.stdio;        " N     N2      enc     dec2 dec".writeln;        foreach (immutable n; 0 .. 32) {            immutable g = n.grayEncode;            immutable d = g.grayDecode;            writefln("%2d: %5b => %5b => %5b: %2d", n, n, g, d, d);            assert(d == n);        }    }

  [9, 4, 3, 8, 5].reduce!max.writeln;

Erlang

  -module(hw).    -export([start/0]).    start() ->       [ spawn(fun() ->  say(self(), X) end) || X <- ['Enjoy', 'Rosetta', 'Code'] ],       wait(2),       ok.    say(Pid,Str) ->       io:fwrite("~s~n",[Str]),       Pid ! done.    wait(N) ->       receive           done -> case N of               0 -> 0;               _N -> wait(N-1)           end       end.

Go

  package main    import (        "fmt"        "math/rand"        "time"    )    func main() {        words := []string{"Enjoy", "Rosetta", "Code"}        rand.Seed(time.Now().UnixNano())        q := make(chan string)        for _, w := range words {            go func(w string) {                time.Sleep(time.Duration(rand.Int63n(1e9)))                q <- w            }(w)        }        for i := 0; i < len(words); i++ {            fmt.Println(<-q)        }    }

Haskell

binarySearch :: Integral a => (a -> Ordering) -> (a, a) -> Maybe a  binarySearch p (low,high)    | high < low = Nothing    | otherwise =        let mid = (low + high) `div` 2 in        case p mid of          LT -> binarySearch p (low, mid-1)          GT -> binarySearch p (mid+1, high)          EQ -> Just mid

Java

  import java.util.List;    import java.nio.charset.Charset;    import java.nio.file.*;    public class ReadAll {        public static List readAllLines(String filesname){            Path file = Paths.get(filename);            return Files.readAllLines(file, Charset.defaultCharset());        }       public static byte[] readAllBytes(String filename){           Path file = Paths.get(filename);           return Files.readAllBytes(file);       }    }

Javascript

  function Car(brand, weight) {      this.brand = brand;      this.weight = weight || 1000;    }    Car.prototype.getPrice = function() {      return this.price;    }    function Truck(brand, size) {      this.constructor(brand, 2000);      this.size = size;    }    Truck.prototype = new Car;    var cars = [      new Car("Mazda"),      new Truck("Volvo", 2)    ];    for (var i=0; i        console.log(cars[i]);        console.log("brand: "+cars[i].brand+". weight: "+cars[i].weight+"." + (( cars[i].hasOwnProperty('size') ) ? " size: "+cars[i].size : ""));        console.log("Car: %s. Truck: %s\n", cars[i] instanceof Car, cars[i] instanceof Truck);    }

  var characters = [      { 'name': 'barney',  'age': 36 },      { 'name': 'fred',    'age': 40 },      { 'name': 'pebbles', 'age': 1 }    ];    var youngest = _.chain(characters)        .sortBy('age')        .map(function(chr) { return chr.name + ' is ' + chr.age; })        .first()        .value();

let n_arrays_iter ~f = function | [] -> () | x::xs as al ->     let len = Array.length x in     let b = List.for_all (fun a -> Array.length a = len) xs in     if not b then invalid_arg "n_arrays_iter: arrays of different length";     for i = 0 to pred len do       let ai = List.map (fun a -> a.(i)) al in       f ai        done

  function hashJoin($table1, $index1, $table2, $index2) {        foreach ($table1 as $s)            $h[$s[$index1]][] = $s;        foreach ($table2 as $r)          foreach ($h[$r[$index2]] as $s)            $result[] = array($s, $r);        return $result;    }    $table1 = array(array(27, "Jonah"),               array(18, "Popeye"),               array(28, "Alan"));    $table2 = array(array("Jonah", "Whales"),               array("Jonah", "Spiders"),               array("Alan", "Ghosts"),               array("Bob", "foo"));    foreach (hashJoin($table1, 1, $table2, 0) as $row)        print_r($row);

  from itertools import islice    def hamming2():        '''\        A text documenting this function (stripped)        '''        h = 1        _h=[h]    # memoized        multipliers  = (2, 3, 5)        multindeces  = [0 for i in multipliers] # index into _h for multipliers        multvalues   = [x * _h[i] for x,i in zip(multipliers, multindeces)]        yield h        while True:            h = min(multvalues)            _h.append(h)            for (n,(v,x,i)) in enumerate(zip(multvalues, multipliers, multindeces)):                if v == h:                    i += 1                    multindeces[n] = i                    multvalues[n]  = x * _h[i]            # cap the memoization            mini = min(multindeces)            if mini >= 1000:                del _h[:mini]                multindeces = [i - mini for i in multindeces]            #            yield h

  hamming = Enumerator.new do |yielder|      next_ham = 1      queues = { 2 => [], 3 => [], 5 => [] }      loop do        yielder << next_ham   # or: yielder.yield(next_ham)        [2,3,5].each {|m| queues[m]<< (next_ham * m)}        next_ham = [2,3,5].collect {|m| queues[m][0]}.min        [2,3,5].each {|m| queues[m].shift if queues[m][0]== next_ham}      end    end    idx = 1    hamming.each do |ham|      case idx      when (1..20), 1691        p [idx, ham]      when 1_000_000        p [idx, ham]        break      end      idx += 1    end

  object HofstadterQseq extends App {      val Q: Int => Int = n => {        if (n <= 2) 1        else Q(n-Q(n-1))+Q(n-Q(n-2))      }      (1 to 10).map(i=>(i,Q(i))).foreach(t=>println("Q("+t._1+") = "+t._2))      println("Q("+1000+") = "+Q(1000))    }

  ;;! Recursive map that applies function to each node    (define (map** f l)      (cond       ((null? l) '())       ((not (pair? l)) (f l))       (else        (cons (f (map** f (car l))) (f (map** f (cdr l)))))))    ;;! Explicit currying of an arbitrary function    (define (curry fun arg1 . args)      (if (pair? args)          (let ((all-args (cons arg1 args)))            (lambda x              (apply fun (append all-args x))))          (lambda x            (apply fun (cons arg1 x)))))    ;;! Implementation of filter, with the match macro    (define (filter p lst)      (match lst       ('() '())       (((? p) . tl) (cons (car lst) (filter/match p tl)))       ((hd . tl) (filter/match p tl))))