Declarative vs imperative:

let v = sum [ ((x ! i) - m) ^ 2 | i <- [0 .. cc - 1] ] / fromIntegral cc

float v = 0.0f;
for (int i = 0; i < C; i++) {
    float xshift = x[i] - m;
    v += xshift * xshift;
}
v = v/C;

#haskell