What will be the output of $a and $b once code bellow is executed?
PHP | output of $a and $b once this code $a = '1'; $b = &$a; $b = "2$b" executed;
Both $a and $b will output a string "21".
Because the statement $b = &$a; sets $b equal to a reference to $a. Thereafter, as long as $b remains a reference to $a, anything done to $a will affect $b and vice versa.
So when the statement $b = "2$b" executes, $b is set equals to string "2" followed by the current value of $b which is 1, so this results of $b sets to string "21" (i.e., the concatenation of "2" and "1"). And, since $b is reference to $a, so any things change to any one will affect both, therefore both $a and $b will output string "21".
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