Fill in the missing code: this recursive method returns "even" if the length of a give string is even, and "odd" if the length of the string is odd.

public static string foo(string s)

{

if (s. length() ==0)
return "even";
else if (s. length() = = 1)
return "odd";
else

//your code goes here

}

(40 pts) you coded the following in the file test. java :
system. out. println( foo(5));
//more code here

public static int foo(int n) //line 9

{

if (n = = 0)
return 1;
else

system. out. println(n* foo(n-1) );

} //line 15

at compile time, you get the following error:
text. java: 15: missing return statement

} //line 15

^

1 error

explain what the problem is and how to fix it.