Compare the Pair

Problem

Read two numbers from input, compare them, and print the greater number.

6. Compare the pair, Comet 64

Solution 1

We read two numbers x and y from input and compare them. If x > y, then the left operand is larger and we print x. Otherwise, x <= y and we print the right operand y.

int = input;           // Read x from input.
reg = input;           // Read y from input.
check int > reg;       // Is x > y?
jump if true: left;    // If true, x is larger.
jump if false: right;  // Otherwise, x <= y.
left:                  // The "left" branch.
    output = int;      // Print x.
    jump to: end;      // Go to "end".
right:                 // The "right" branch.
    output = reg;      // Print y.
end:                   // End of program.

Solution 2

Similar to Solution 1. We can eliminate some lines from the previous solution by noticing that we do not need a jump instruction when the conditional x > y is false. If the conditional x > y is true, we jump to the branch that prints x. Otherwise, we print y without having to jump to a different branch. This solution is optimal, according to the game.

int = input;          // Read x from input.
reg = input;          // Read y from input.
check int > reg;      // Is x > y?
jump if true: print;  // If so, go to "print".
int = reg;            // Otherwise, set int to value of reg.
print:                // The "print" branch.
    output = int;     // Print the larger number.