(5) Suppose the following program H existed.

(5) Suppose the following program H existed.

/* Program H. */

static void main(String [] args)

{

TokenReader in = new TokenReader(System.in);

String s = in.readString()

boolean b;

/* Set b==true if s is a program that loops when

given s as input, else set b==false. */

...

if ( b ) System.out.println("loops");

else System.out.println("halts");

}

Note that for every possible input s, program H prints a message and halts.

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