Hellow!

I want to make a very easy sound programm but as a newbie there's nothing easy in its beginnings ;)

Idea_ The higher the mouse the higher the frequency. I tried following but I got this error message:
"the local variable freq may not have bee initialised".

Probably there's something wring with the order?

1. float c = 261.63;
2. float cs = 277.18;
3. float[] notas = {c, cs,};
4. void mouseMoved() {
5.   
6.   int c = 262;
7.   int cs = 277;
8.  
9.   float freq;
10.  
11.   if (mouseY<c) {
12.   freq = notas [1]; }
13.  
14.   if (mouseY<cs) {
15.   freq = notas [2]; }
16.  
17.   sine.setFreq(freq);
18. }