first of all i am doing programs in java language this code is merely taken from web site i have not question about divide and conqurer algorithms but about function and it's argument here is code of ternary search

def ternarySearch(f, left, right, absolutePrecision):
    #left and right are the current bounds; the maximum is between them
    if (right - left) < absolutePrecision:
        return (left + right)/2

    leftThird = (2*left + right)/3
    rightThird = (left + 2*right)/3

    if f(leftThird) < f(rightThird):
        return ternarySearch(f, leftThird, right, absolutePrecision)

    return ternarySearch(f, left, rightThird, absolutePrecision)

i am not asking once again how implement it in java i am asking for example how define function?for example let y=x^+3 yes we can determine it as

public static int y(int x){
 return x*x+3;
}

but here

 return ternarySearch(f, leftThird, right, absolutePrecision)

function f does not have argument and how do such?please help me