还是回复一下代码吧，过了90%，纯粹抛砖引玉 #include <iostream> (720)#include<vector> #include<algorithm> using namespace std; int n; double x, y; double helper(double& x1, double& x2, double& y1, double& y2) { return min((x1 + x2) / 2, (y1 + y2) / 2); } int main() { double x1, x2; double y1, y2; double res; while (cin >> n) { cin >> x1 >> y1 >> x2 >> y2; double t1, t2; x = (x1 + x2) / 2; y = (y1 + y2) / 2; res = helper(x1, x2, y1, y2); for (int i = 2; i < n; ++i) { cin >> t1 >> t2; double tmp = helper(x1, t1, y1, t2); if (tmp > res) { res = tmp; x2 = t1; y2 = t2; } tmp = helper(x2, t1, y2, t2); if (tmp > res) { res = tmp; x1 = t1; y1 = t2; } } cout << res << endl; } return 0; }