C++: Maximum of three numbers(function)

#include<iostream.h>

int max(int x,int y ,int z)

{

            if(x>y&&x>z) return x;

            else if (y>x&&y>z)return y;

            else if (z>x&&z>y)return z;

}

int main()

{

            int x,y,z,m;

cout<<"enter x"<<endl;cin>>x;

cout<<"enter y"<<endl;cin>>y;

cout<<"enter z"<<endl;cin>>z;

m=max(x,y,z);

cout<<"Max is"<<m;

return 0;

}