Program breakdown

Here’s an overview of what each of the lines in our ‘Hello world’ program mean. For a more thorough explanation, you may wish to explore the Language syntax.

int a, b, c

This line declares three integers named ‘a’, ‘b’ and ‘c’. Integers can be both positive and negative numbers.

invariant a + b + c == 10;

This line captures what we are trying to do. We want to find three numbers that add to 10 and this line specifies this an invariant of the program, i.e. that this is something that must always be true.

invariant a > 0, b > 0, c > 0;

As mentioned above, integers can be negative. This line adds another invariant that rules out negatives. We didn’t need to do this, but it serves as an interesting example.

expose a, b, c;

This line makes it so that ‘a’, ‘b’ and ‘c’ all appear in the program output when it runs. Variables must be explicitly exposed from Sentient programs.