public class ArrayCopyExample {
public static void main(String[] args) {
// æ–‡å—列型ã®é…列 names を宣言ã—ã€è¦ç´ æ•°ãŒ3ã§åˆæœŸåŒ–
String[] names = new String[3];
// é…列 names ã«å¥½ããªåå‰ã‚’代入
names[0] = "Alice";
names[1] = "Bob";
names[2] = "Charlie";
// åˆ¥ã®æ–‡å—列型ã®é…列 copyNames を宣言ã—ã€è¦ç´ æ•°ãŒ3ã§åˆæœŸåŒ–
String[] copyNames = new String[3];
// names ã®å†…容を copyNames ã«ã‚³ãƒ”ー
for (int i = 0; i < names.length; i++) {
copyNames[i] = names[i];
}
// copyNames ã®å†…容を表示
System.out.print("copyNames: ");
for (String name : copyNames) {
System.out.print(name + " ");
}
}
}
ã“ã®ãƒ—ãƒã‚°ãƒ©ãƒ ã§ã¯ã€names ã¨ã„ã†åå‰ã®æ–‡å—列型ã®é…列を宣言ã—ã€å¥½ããªåå‰ã‚’手動ã§ä»£å…¥ã—ã€copyNames ã¨ã„ã†åå‰ã®åˆ¥ã®æ–‡å—列型ã®é…列ã«ã‚³ãƒ”ーã—ã¦ã„ã¾ã™ã€‚最後ã«ã€copyNames ã®å†…容を表示ã—ã¦ã„ã¾ã™ã€‚
æ–‡å—列型ã®é…列変数間ã§ã®ä»£å…¥
æ–‡å—列型ã®é…列変数間ã§ã®ä»£å…¥ã¯ã€ä¸€ã¤ã®æ–‡å—列型ã®é…列ã‹ã‚‰åˆ¥ã®æ–‡å—列型ã®é…列ã«ãƒ‡ãƒ¼ã‚¿ã‚’コピーã™ã‚‹æ“作ã§ã™ã€‚以下ã¯ã€æ–‡å—列型ã®é…列変数間ã§ã®ä»£å…¥ã«é–¢ã™ã‚‹è§£èª¬ã§ã™ã€‚
é…列ã®å®£è¨€ã¨åˆæœŸåŒ–:
ã¾ãšã€å…ƒã®æ–‡å—列型ã®é…列を宣言ã—ã€è¦ç´ 数を指定ã—ã¦åˆæœŸåŒ–ã—ã¾ã™ã€‚ã“ã®é…列ã«ãƒ‡ãƒ¼ã‚¿ã‚’æŒãŸã›ã¾ã™ã€‚
String[] names = new String[3];
ã“ã®ã‚³ãƒ¼ãƒ‰ã§ã¯ã€names ã¨ã„ã†åå‰ã®æ–‡å—列型ã®é…列を宣言ã—ã€è¦ç´ æ•°ãŒ3ã®æ–°ã—ã„é…åˆ—ã‚’åˆæœŸåŒ–ã—ã¦ã„ã¾ã™ã€‚
データã®ä»£å…¥:
次ã«ã€å…ƒã®é…列ã«ãƒ‡ãƒ¼ã‚¿ã‚’代入ã—ã¾ã™ã€‚ã“ã‚Œã¯æ‰‹å‹•ã§è¡Œã†ã“ã¨ãŒã§ãã¾ã™ã€‚è¦ç´ ã”ã¨ã«ãƒ‡ãƒ¼ã‚¿ã‚’代入ã™ã‚‹ã«ã¯ã€æ·»ãˆå—(インデックス)を使用ã—ã¾ã™ã€‚
names[0] = "Alice";
names[1] = "Bob";
names[2] = "Charlie";
ã“ã®ã‚³ãƒ¼ãƒ‰ã§ã¯ã€names ã®å„è¦ç´ ã«å¥½ããªåå‰ã‚’代入ã—ã¦ã„ã¾ã™ã€‚
æ–°ã—ã„é…列ã®å®£è¨€ã¨åˆæœŸåŒ–:
åˆ¥ã®æ–‡å—列型ã®é…列変数を宣言ã—ã€è¦ç´ 数を指定ã—ã¦åˆæœŸåŒ–ã—ã¾ã™ã€‚ã“れã¯ã€ãƒ‡ãƒ¼ã‚¿ã‚’コピーã™ã‚‹ãŸã‚ã®å—ã‘入れ先ã¨ãªã‚‹é…列ã§ã™ã€‚
String[] copyNames = new String[3];
ã“ã®ä¾‹ã§ã¯ã€æ–°ã—ã„æ–‡å—列型㮠copyNames を宣言ã—ã€è¦ç´ æ•°ãŒ3ã®æ–°ã—ã„é…åˆ—ã‚’åˆæœŸåŒ–ã—ã¦ã„ã¾ã™ã€‚
データã®ã‚³ãƒ”ー:
最後ã«ã€å…ƒã®é…列ã‹ã‚‰æ–°ã—ã„é…列ã«ãƒ‡ãƒ¼ã‚¿ã‚’コピーã—ã¾ã™ã€‚ã“れã¯ãƒ«ãƒ¼ãƒ—を使用ã—ã¦è¡Œã†ã“ã¨ãŒä¸€èˆ¬çš„ã§ã™ã€‚å„è¦ç´ ã‚’é †ç•ªã«ã‚³ãƒ”ーã—ã¾ã™ã€‚
for (int i = 0; i < names.length; i++) {
copyNames[i] = names[i];
}
ã“ã®ãƒ«ãƒ¼ãƒ—ã¯ã€names ã®å„è¦ç´ ã‚’ copyNames ã«ã‚³ãƒ”ーã—ã¾ã™ã€‚
ã“ã‚Œã‚‰ã®æ‰‹é †ã«å¾“ã†ã“ã¨ã§ã€æ–‡å—列型ã®é…列変数間ã§ãƒ‡ãƒ¼ã‚¿ã‚’効果的ã«ã‚³ãƒ”ーã™ã‚‹ã“ã¨ãŒã§ãã¾ã™ã€‚
「0004 é…列ã€å•題集リスト
🎯 実習ã§ç†è§£ã‚’æ·±ã‚よã†
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