paizaラーニングレベルアップ問題集の「配列のサイズの変更」をやってみた。

paizaラーニングレベルアップ問題集の配列のサイズの変更をやってみました。

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問題

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Visual Basic系では

ReDim Preserve A(m-1)

というものがあります。
それ相応の関数やメソッドのない言語の場合、$n>N$の場合には全要素0・長さ$n-N$の配列を結合する方法もあります。

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C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main() {
	int N, n;
	scanf("%d %d", &N, &n);
	int *A = malloc(sizeof(int) * N);
	for (int i = 0; i < N; i++) scanf("%d", &A[i]);
	A = realloc(A, sizeof(int) * n);
	if (n > N) memset(A + N, 0, sizeof(int) * (n - N));
	for (int i = 0; i < n; i++) printf("%d\n", A[i]);
	return 0;
}

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C++

#include <iostream>
#include <vector>
using namespace std;

int main() {
	int N, n;
	cin >> N >> n;
	vector<int> A(N);
	for (int i = 0; i < N; i++) cin >> A[i];
	A.resize(n);
	for (int i = 0; i < n; i++) cout << A[i] << endl;
	return 0;
}

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C#

using System;
using System.Linq;

class Program
{
	public static void Main()
	{
		int[] Nn = Array.ConvertAll(Console.ReadLine().Split(), int.Parse);
		int N = Nn[0], n = Nn[1];
		int[] A = Enumerable.Range(0, N).Select(_ => int.Parse(Console.ReadLine())).ToArray();
		Array.Resize(ref A, n);
		for (int i = 0; i < n; i++) Console.WriteLine(A[i]);
	}
}

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Go

package main
import "fmt"

func main() {
	var N, n int
	fmt.Scan(&N, &n)
	A := make([]int, N)
	for i := 0; i < N; i++ {
		fmt.Scan(&A[i])
	}
	if n < N {
		A = A[:n]
	} else if n > N {
		A = append(A, make([]int, n - N)...)
	}
	for i := 0; i < n; i++ {
		fmt.Println(A[i])
	}
}

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Java

import java.util.*;
import java.util.stream.*;

public class Main {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int n = sc.nextInt();
		int[] A = IntStream.range(0, N).map(__ -> sc.nextInt()).toArray();
		sc.close();
		A = Arrays.copyOf(A, n);
		for (int i = 0; i < n; i++) System.out.println(A[i]);
	}
}

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JavaScript

let [[N, n], ...A] = require("fs").readFileSync("/dev/stdin", "utf8").trim().split('\n').map((s, i) => i ? Number(s) : s.split(' ').map(Number));
A.length = n;
for (var i = N; i < n; i++) A[i] = 0;
for (var i = 0; i < n; i++) console.log(A[i]);

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Kotlin

fun main() {
	val (N, n) = readLine()!!.split(" ").map { it.toInt() }
	var A = Array(N) { readLine()!!.toInt() }
	if (n < N) A = A.toList().take(n).toTypedArray()
	else if (n > N) A = A.plus(Array(n - N) { 0 })
	for (i in 0 until n) println(A[i])
}

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PHP

<?php
	[$N, $n] = array_map("intval", explode(' ', fgets(STDIN)));
	$A = [];
	for ($i = 0; $i < $N; $i++) $A[] = intval(fgets(STDIN));
	if ($n < $N) array_splice($A, $n);
	else if ($n > $N) array_splice($A, $N, 0, array_fill(0, $n - $N, 0));
	for ($i = 0; $i < $n; $i++)	echo $A[$i], PHP_EOL;
?>

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Perl

my ($N, $n) = map { int($_) } split ' ', <STDIN>;
my @A;
for (1..$N) {
	push @A, int(<STDIN>);
}
if ($n < $N) {
	splice @A, $n;
} elsif ($n > $N) {
	splice @A, $N, 0, (0) x ($n - $N);
}
for (my $i = 0; $i < $n; $i++) {
	print $A[$i], $/;
}

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Python3

N, n = map(int, input().split())
A = [int(input()) for _ in range(N)]
A = A[:n] + [0] * max(0, n - N)
for i in range(n):
	print(A[i])

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Ruby

N, M = gets.split.map(&:to_i)
a = N.times.map { gets.to_i }
a = a[...M] + [0] * [0, M - N].max
M.times do |i|
	p a[i]
end

---

Scala

import scala.io.StdIn._

object Main extends App{
	val Array(n, m) = readLine().split(' ').map { _.toInt }
	var A = (0 until n).map { _ => readInt() }
	if (m < n) A = A.take(m)
	else if (m > n) A = A ++ Array.fill(m - n)(0)
	for (i <- 0 until m) println(A(i))
}

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Swift

let Nn = readLine()!.split(separator: " ").compactMap { Int($0) }
let (N, n) = (Nn[0], Nn[1])
var A = (0..<N).map { _ in Int(readLine()!)! }
if n < N {
	A = Array(A.prefix(n))
} else if n > N {
	A += Array<Int>(repeating: 0, count: n - N)
}
for i in 0..<n {
	print(A[i])
}

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VB.NET

Imports System

Module Main
	Sub Main()
		Dim nm() As String = Console.ReadLine.Split
		Dim n As Integer = Integer.Parse(nm(0))
		Dim m As Integer = Integer.Parse(nm(1))
		Dim A(n-1) As Integer
		For i As Integer = 0 to n - 1
			A(i) = Integer.Parse(Console.ReadLine)
		Next
		ReDim Preserve A(m-1)
		For i As Integer = 0 To m - 1
			Console.WriteLine(A(i))
		Next
	End Sub
End Module