#include <bits/stdc++.h> using namespace std; int main() { int a, b; int c, d; cin >> a >> b; cin >> c >> d; double e=sqrt((a - c)*(a - c) + (b - d)*(b - d)); double f=fabs(a - c) +fabs(b - d); double g=fabs(e - f); cout << fixed << setprecision(7) << ...