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  • Haskell

Idiom #42 Continue outer loop

Print each item v of list a which is not contained in list b.
For this, write an outer loop to iterate on a and an inner loop to iterate on b.

Control flow jumping back to the beginning of the outermost loop 
sequence_ [ print v | v <- a, [ u | u <- b, u == v] == [] ]

a _\\ b abbreviates this task if you are not required to write your own printing iterations

Our outer loop continues to the next element whenever the inner list equality test breaks the inner iteration lazily after the first of any [u|u==w] found growing too large to equal [].
int *v = a;
while (v < a+N)
{
    int *w = b;
    while (w < b+M)
    {
        if (*v == *w)
            goto OUTER;
        
        ++w;
    }
    printf("%d\n", *v);
    
    OUTER: ++v;
}

N is the length of a.
M is the length of b.

Using goto is usually considered bad practice in C.
New implementation...
< > ⌨
programming-idioms.org 
sequence_ [ print v | v <- a, [ u | u <- b, u == v] == [] ]
int *v = a;
while (v < a+N)
{
    int *w = b;
    while (w < b+M)
    {
        if (*v == *w)
            goto OUTER;
        
        ++w;
    }
    printf("%d\n", *v);
    
    OUTER: ++v;
}
auto a = {1,2,3,4,5};
auto b = {3,5};

for (auto va: a){
    for (auto vb: b){
        if (va==vb) goto OUTER;
    }
    std::cout << va << '\n';
    OUTER: continue;
}
int gb = 0;
foreach (int v in a)
{
  foreach (int w in b)
  {
    gb = w;
    if (w == v)
      break;
  }
  if (gb == v)
    continue;
  System.Console.WriteLine(v);
}
auto a = [1,2,3,4,5];
auto b = [3,5];

void main()
{
mainloop:
	foreach(v;  a){
		foreach(w; b){
			if(v == w) continue mainloop;
		}
		writeln(v);		 
	}
}

main()  {
  var a = [1, 2, 3];
  var b = [2, 3];

  outer: for (var v in a) {
    for (var w in b) {
      if (w == v) continue outer;
    }
    print(v);
  }
}

  outer: do i=1,size(a)
     do j=1,size(b)
        if (a(i) == b(j)) cycle outer
     end do
     print *,a(i)
  end do outer
mainloop:
	for _, v := range a {
		for _, w := range b {
			if v == w {
				continue mainloop
			}
		}
		fmt.Println(v)
	}
OUTER:
for (var i in a) {
   for (var j in b) {
      if (a[i] === b[j]) {
         continue OUTER;
      }
   }
   console.log(a[i] + " not in the list");
}
mainloop: for(int v:a){
	for(int w:b){
		if(v==w)
			continue mainloop;
	}
	System.out.println(v);
}
$array_1 = [1,2,3,4,5];
$array_2 = [3,4];

foreach ($array_1 as $a) {
    foreach ($array_2 as $b) {
        if ($b == $a) {
            continue 2;
        }
    }
    echo $a
}
  for v in a do
    begin
      for  w in b do
        if (v = w) then
          break;
      if (v = w) then
        Continue;
      writeln(v);
    end;              
OUTER:
for my $v (@a) {
   for my $check (@b) {
      next OUTER if $v == $check;
   }
   print "$v not in the list\n";
}
      
for v in a:
    try:
        for u in b:
            if v == u:
                raise Exception()
        print(v)
    except Exception:
        continue

for v in a:
  keep = True
  for w in b:
    if w == v:
      keep = False
      break
  if keep:
    print(v)
z = False
for x in a:
    for y in b:
        if y == x:
            z = True
            break
    if not z: print(x)
    z = False
a.each do |v|
  catch :matched do
    b.each do |u|
      throw :matched if v == u
    end
    puts v
  end  
end
'outer: for va in &a {
    for vb in &b {
        if va == vb {
            continue 'outer;
        }
    }
    println!("{}", va);
}