A certain computation generates two arrays a and b such that a[i]=f(i)for 0 ≤ i < n and b[i] = g (a[i] )for 0 ≤ i < n. Suppose this computation is decomposed into two concurrent processes X and Y such that X computes the array a and Y computes the array b. The processes employ two binary semaphores R and S, both initialized to zero. The array a is shared by the two processes. The structures of the processes are shown below.

Process X:
private i;
for(i = 0; i < n; i++){
 a [i] = f (i);
 Exit X (R, S);
}

Process Y:
private i;
for(i = 0; i < n; i++){
 Entry Y (R, S);
 b [i] = g (a [i] );
}

Which of the following represents the correct implementations of Exit X and Entry Y?

What is the return value of f (p, p), if the value of p is initialized to 5 before the call? Note that the first parameter is passed by reference, whereas the second parameter is passed by value.

int f (int &x, int c) {
    c = c - 1;
    if (c==0) return 1;
    x = x + 1;
    return f(x,c) * x;
}

The following figure represents access graphs of two modules $$M1$$ and $$M2.$$ The filled circles represent methods and the unfilled circles represent attributes. If method m is moved to module $$M2$$ keeping the attributes where they are, what can we say about the average cohesion and coupling between modules in the system of two modules?

The procedure given below is required to find and replace certain characters inside an input character string supplied in array $$A.$$ The characters to be replaced are supplied in array $$oldc,$$ while their respective replacement characters are supplied in array $$newc.$$ Array $$A$$ has a fixed length of five characters, while arrays $$oldc$$ and $$newc$$ contain three characters each. However, the procedure is flawed. void find_and_replace (char $$^ * A,$$ char $$^ * oldc,$$, char $$^ * newc$$)
$$\left\{ \, \right.$$ for (int $$i=0; i<5; i++$$)
for (int $$j=0; j<3; j++$$)
if ( $$A$$ [ $$i$$ ] $$==oldc$$ [ $$j$$ ] $$A$$ [ $$i$$ ]
$$=newc$$ [ $$j$$ ]; $$\left. \, \right\}$$

The procedure is tested with the following four test cases;
$$\eqalign{ & \left( 1 \right)\,\,\,oldc = ''abc'',\,\,newc\, = \,''dab'' \cr & \left( 2 \right)\,\,\,oldc\, = \,''cdc'',\,\,newc\, = \,''bed'' \cr & \left( 3 \right)\,\,\,oldc\, = \,''bca'',\,newc\, = \,''cda'' \cr & \left( 4 \right)\,\,\,oldc\, = \,''abc'',\,newc\, = \,''bac'' \cr} $$

The tester now tests the program on all input strings of length five consisting of characters $$'a', 'b', 'c', 'd'$$ and $$'c'$$ with duplicates allowed. If the tester carries out this testing with four test cases given above, how many test cases will be able to capture the flaw?