求助！为什么本地答案正确，线上的全红了

#include<iostream>
#include<math.h>
using namespace std;
class Position
{
public:
    int x;
    int y;
};
int Distance(Position a, Position b )
{
    int dis = 0;
    dis = (a.x - b.x) * (a.x - b.x) + (a.y - b.y) * (a.y - b.y);
    dis = sqrt(dis);
    return dis;
}

int main()
{
    Position a, b, c;
    cin >> a.x>>a.y;
    cin >> b.x >> b.y;
    cin >> c.x >> c.y;
    int dis1 = Distance(a, b);
    int dis2 = Distance(a, c);
    int dis3 = Distance(b, c);
    float Dis=(float)( dis1 + dis2 + dis3);
    printf("%.2f", Dis);
    return 0;
}