问答题

本题程序功能是分别比较两个字符串"A"和"a"是否相等及两个字符’A’和’a’是否相等，并输出比较结果。请将下述程序补充完整(注意：不得改动程序的结构，不得增行或删行)。
public class basic

public static void main (String[] args)

______;
c1= ’A’;c2 = ’a’;
String str1= new String("A"),str2 = new String("a");
if(______)
System.out.println(c1+" equals "+c2);
else
System.out.println(c1+" doesn’t equal "+c2);
if(______)
System.out.println(str1+" equals "+str2);
else
System.out.println(str1+" doesn’t equal "+str2);

【参考答案】

 char cA,cB。
cA=cB。
strA.equals(strB)。

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