#include "std.alpha"

function entry : string2integer
function fib : integer2integer

fib(i) := {
    [ integer: a; integer: b; integer: count ]
    
    a := 1;
    b := 2;

    if (i = 0) then {
        return 0;
    } else {
        a := a;
    }

    if (i = 1) then {
        return 1;
    } else {
        a := a;
    }

    if (i = 2) then {
        return 2;
    } else {
        a := a;
    }

    count := 2;
    while (count < i) {
        
        count := count + 1;
    }

    return b;
}

entry (arg) := {
    [ integer: result; integer: input; integer: fibValue]

    result := printC('E');
    result := printC('n');
    result := printC('t');
    result := printC('e');
    result := printC('r');
    result := printC(' ');
    result := printC('N');
    result := printC('u');
    result := printC('m');
    result := printC('b');
    result := printC('e');
    result := printC('r');
    result := printC(':');
    result := printC(' ');

    input := inI(1);
    fibValue := fib(input);
    
    result := printI(fibValue);

    return 0;
}