CSCI 152 Preliminary Quiz ( 30 Aug ) Possible Answers

Fall 2004

1. Given the following declarations, mark each of the boolean expressions as either true (T) or false (F):

int a=5;

int b=10;

int c = 7;

T F (a > b)

T F (b == 10)

T F (a + c > b)

T F (a < b) && (c < b)

T F (a == 10) || (c == 10)

2. Using the same variable declarations from 3 above, what do the following statements print.

if (c+b < 20)

{

if (b == 5)

{

cout << “Location 1”

}

else if (b == 8)

{

cout << “Location 2”

}

else

{

cout << “location 3”

}

}

else

{

cout << “location 4”

}

location 3

for (int i=0; i<a; i++)

{

cout << i*i << “ “;

}

0 1 4 9 16

int x=9;

while (x >= c)

{

cout << x << “ “;

x = x – 1;

}

9 8 7

3. a) Write a function which takes two integer parameters and returns the smaller of the two.

int min(int first, int second) or int min(int first, int second)

{ {

if (first < second) if (first < second)

return first; return first;

else return second;

return second; }

}

or int min(int first, int second)

{

int smaller;

if (first < second)

smaller = first;

else

smaller = second;

return smaller;

}

b) Call the function you wrote in (a) and display the larger of x and y.

if (min(x,y) == x) or int smaller = min(x, y)

cout << y; if (smaller == x)

else cout << y;

cout << x; else

cout << x;

4. Given these declarations: int a[100];

int oddSum;

int n;

Write a loop to calculate the sum of the odd-numbered elements (elements 1, 3, etc.) of a, storing this result in the variable oddSum.

You may assume that appropriate values have been assigned to all elements of the array.

oddSum = 0; or oddSum = 0;

for (n=1; n<100; n+= 2) n = 1;

oddSum += a[n]; while (n < 100)

{

oddSum = oddSum + a[n];

n = n + 2;

or }

oddSum = 0;

for (n=1; n<100; n++)

if (n % 2 == 1) // a[n]% 2 would check for the array value itself being odd

oddSum += a[n];

Note: for (n=1; n<100; n = n+2) is okay for the first version instead of n += 2

but for (n=1; n<100; n+2) wouldn’t actually change the value of n