Calculate the values of variables a and b after the call to

Calculate the values of variables a and b after the call to the subprogram guessWhat returns, where a is a global variable and b is local to the caller. Assume that all parameters are passed by pass-by-name, and 0-based indices are used for arrays.

// global variable
int[] a = new int[] { 10, 20 };

// subprogram void guessWhat(int x, int y) {
   x = (x + 2) % 2;
y = (y + 2) % 2;
     a[x] = a[y] + 1;
}
// caller
int b = 1;
guessWhat(b, a[b]);

Solution

before passing the bariable values to the method guessWhat(b,a[b]) as inputs

the value of b is 1 , and

the value of a[b] is 20

the when we call the method guessWhat(b,a[b]) by passing the values guessWhat(1,20) as input arguments

then inside the that method some oprations is performed

guessWhat(int x,int y) here we are passing the value of b to x and a[b] to y

x=(x+2)%2;

x=(1+2)%2

x=3%2

x=1 (when divided by 3 with 2 the remainder is 1)

y = (y + 2) % 2;

y=(20+2)%2

y=22%2

y=0(when divided by 22 with 2.The remainder is zero)

a[x]=a[y]+1;

a[1]=a[0]+1(as x=1 and y=0)

a[1]=10+1

a[1]=11

then a[1] will be overridden by the value 11

then after the sub program got executed the value of b is 1

and the value of a[b] is 11

_____________Thank You