大神求改错！！！

#include <iostream>
#include"Point.h"
using namespace std;
int main(void) {
Point juli;
juli.init(a,b);
juli.up(a,b);
cout<<juli<<endl;
return 0;
}
class Point
{
public:
void init(int a,int b,int juli);
void up(int a,int b);
public:
int a_;
int b_;
double juli_;
};
void Point::init(int a,int b,int juli)
{
a_=a;
b_=b;
juli_=juli;
}
void Point::up(int a,int b)
{
cin>>a>>b;
juli=sqrt(a*a+b*b);
cout<<juli_<<endl;
}