ICode9

牛客小白月赛55 A-E https://ac.nowcoder.com/acm/contest/38630 F待补 解析啥的睡醒再补，先放个代码 A - 至至子的等差中项 #include <bits/stdc++.h> using namespace std; int main () { int a, b; cin >> a >> b; cout << 2*b-a; } B - 至至子的按位与 #includ