** On paper portion.
Points: 20 points total, 10 points for #1, 10 points for #2

Last Name:


First Name: 


Section (start time of your class): 



1) Run the algorithm.  Use the indicated algorithm to answer each question.
   Show your work.  No credit if you don't show your work.

1a) Use selection sort to sort the numbers  7, -1, -2, 3, 0, 5














1b) Encrypt the message "what fun" using the caesar cipher and
    password 20 (shift each letter by 20 to the right).














1c) Convert the decimal number 144 to binary.










1d) Determine if the number 91 is prime.
















2) Be the computer.  For each, keep track of the values of all the variables
   as the code runs - as we did in class.  


2a) loops.

// code
int i, x=1, total=0;
for(i=1; i < 4; i++) {
  x = x * i;
  total += x;
}


// variable values.
//
// i: 
//
// x: 
//
// total: 
//

















2b) functions.

// code
int f1(int x, int y) {
  y = x - y;
  x = y / 2;
  return x;
}
int f2(int z, int w) {
  z = w + z;
  return f1(z, w);
}
int main() {
  int x, y, z;
  x = f2(1, 2);
  y = f1(x, x);
  z = f1(x, y);
}

// variable values.
//
// x in main:
//
// y in main:
//
// z in main:
//
// x in f1:
//
// y in f1:
//
// z in f2:
// 
// w in f2;



2c) arrays.

// code
double nums[5];
int i;
for(i=0; i<5; i++) {
  nums[i] = i*i;
}
for(i=1; i<5; i++) {
  nums[i] = nums[i] - nums[i-1];
}


// variable values.
//
// i:
//
// nums:
//