可以发现,f([l,r])迭代到倒数第二层,会变成f(f([l,r−1]),f([l+1,r]))=f([l,r−1])⊕f([l+1,r]) #include<iostream> #include<string> #include<math.h> #include<algorithm> #include<vector> //#include<bits/stdc++.h> typedef long long ll; ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; } l...