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Programming-Idioms

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Idiom #284 Create a zeroed list of integers

Create a new list a (or array, or slice) of size n, where all elements are integers initialized with the value 0.

import static java.util.stream.IntStream.iterate;
int a[] = iterate(0, i -> 0).limit(n).toArray();
import static java.util.stream.IntStream.range;
int a[] = range(0, n).map(i -> 0).toArray();
import java.util.stream.IntStream;
int[] a = IntStream.generate(() -> 0)
                .limit(n)
                .toArray();

IntStream from java 8.
Box after limit to create a List<Integer>.
import static java.util.stream.IntStream.range;
import java.util.ArrayList;
import java.util.List;
List<Integer> a = new ArrayList<>(n);
range(0, n).forEach(i -> a.add(0));
import static java.util.Arrays.fill;
Integer a[] = new Integer[n];
fill(a, 0);
int a[] = new int[n];

The default `int` value in Java, is 0.
int[] a = new int[n];

Java automatically initializes integer arrays with zeros.
import java.util.*;
List<Integer> a = new ArrayList<Integer>(n);
for (int i =0;i<n;i++){
    a.add(0);
}
#include <stdlib.h>
int *a = calloc(n, sizeof(*a));

calloc automatically sets every byte allocated to 0.
New implementation...
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programming-idioms.org 
int a[] = iterate(0, i -> 0).limit(n).toArray();
int a[] = range(0, n).map(i -> 0).toArray();
int[] a = IntStream.generate(() -> 0)
                .limit(n)
                .toArray();
List<Integer> a = new ArrayList<>(n);
range(0, n).forEach(i -> a.add(0));
Integer a[] = new Integer[n];
fill(a, 0);
int a[] = new int[n];
int[] a = new int[n];

List<Integer> a = new ArrayList<Integer>(n);
for (int i =0;i<n;i++){
    a.add(0);
}
int *a = calloc(n, sizeof(*a));
(def a (repeatedly n #(identity 0)))
std::vector<int> a(n, 0);
var a = new int[n];
var a = List.filled(n, 0);
integer, dimension(:), allocatable :: a

allocate(a(n),source = 0)
a := make([]int, n)
a = replicate n 0
const a = new Array(n).fill(0);
local function new_zeroed_list(n)
 local ret={}
 for i=1,n do
  ret[i]=0
 end
 return ret
end
local zeroed_list=new_zeroed_list(n)
a := nil;
setlength(a, n);
my @a = (0) x $n;
a = [0] * n
a = [*repeat(0, n)]
a = [0] * n
a = Array.new(n, 0)
let a = vec![0; n];