needed data structure help

[just79]

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Hi all,
can anyone help me with this? i need to know the java programe for this Question




_write a program that determines whether an input string is palindrome;that is whether it can be read the same way forward & backward .at each point you can read only one character of the input string;do not use an array to first store this string and then analyze it(expect,possibly,in a stack implementation).consider using multiple stack




_write a recursive method gcd(n,m)that return the greatest common dividor of two integer n & m



i hope some2 can do it , its so important 2 me ><
thanx in advance .

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