第一题数组随机移除一个元素,求两次移除刚好是左右两端的概率 static void solve() throws IOException { int n = in.nextInt(); double res = 1.0; // if (n == 2) {out.printf("%.10f\n", res); return;} // 1/n * 1/(n-1) * C(2, 1) res = 2.0 / n / (n - 1); out.printf("%.10f...