Constant Pool

Java

String s1 = "Hello";
String s2 = s1;
String s3 = "Hello";
String s4 = new String("Hello");
String s5 = s4;
String s6 = new String("Hello");

System.out.println(s1 == s2);       // true
System.out.println(s1 == s3);       // true
System.out.println(s2 == s3);       // true
		
System.out.println(s4 == s5);       // true
System.out.println(s4 == s6);       // false
System.out.println(s5 == s6);       // false

C/C++

char * s1 = "abcd";
char * s2 = "abcd";
char s3[] = "abcd";
char s4[] = "abcd"; 

printf("%d\n", s1 == s2);       // true
printf("%d\n", s3 == s4);       // false