remove elements

class Solution {
public:
    int removeElement(int A[], int n, int elem) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int step = 0;
        for(int i=0;i<n;i++)
        {        
            if( step > 0 && A[i]!=elem)
                A[i-step] = A[i];
            if( A[i] == elem )
                step ++;
        }
        return n - step;
    }
};