Difference between revisions of "Variable parameter"
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=== XOR swap === | === XOR swap === | ||
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procedure XorSwap( var i,j:integer ); | procedure XorSwap( var i,j:integer ); | ||
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end; | end; | ||
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=== OrderSmallBig === | === OrderSmallBig === | ||
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procedure OrderSmallBig( var a,b:integer ); | procedure OrderSmallBig( var a,b:integer ); | ||
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end; | end; | ||
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== Read more == | == Read more == | ||
Revision as of 15:06, 24 March 2012
Variable parameter (or Reference Parameter) is input and output parameter meaning it can be used for passing a value to a function or a procedure as well as to get back a value from function or procedure. It indicated by the use of the keyword var in front of the formal parameter.
Variable parameter given a new nickname. The method refers to the same variable and changes made will affect the actual variable.
XOR swap
procedure XorSwap( var i,j:integer );
begin
i := i xor j ;
j := i xor j ;
i := i xor j ;
end;OrderSmallBig
procedure OrderSmallBig( var a,b:integer );
begin
if a > b then XorSwap( a, b );
end;