1 #include <bits/stdc++.h> 2 using namespace std; 3 int main() { 4 double x1, y1, x2, y2; 5 cin >> x1 >> y1 >> x2 >> y2; 6 if (x1 == x2) { 7 cout << "INF" << endl; 8 } else { 9 cout << (y2 - y1) / (x2 - x1) << endl; 10 } 11 return 0; 12 }
原文：https://www.cnblogs.com/fx1998/p/12683724.html