Error: expression cannot be used as a function?

Question

I created a quick method in my program to compute the distance between two points using the distance formula, here's the code:

#include <iostream>
#include <cmath>

using namespace std;

int distanceFormula(int x1, int y1, int x2, int y2) {
    double d = sqrt((x1-x2)^2(y1-y2)^2);
    return d;
}

it gives me a compiler error on the line where I declare the d variable saying that

error: expression cannot be used as a function.

What does this mean? And what am I doing wrong?

Answer 1

Be careful, (x1-x2)^2 will not do an exponent of 2 here. See http://www.cplusplus.com/reference/cmath/pow/.

Second, you probably forgot a + in your expression:

int distanceFormula(int x1, int y1, int x2, int y2) {
    double d = sqrt(pow(x1-x2, 2) + pow(y1-y2, 2));
    return d;
}