\(A\) 传送门 用哈希表去下重即可。 #include <iostream> #include <cstdio> #include <cstring> using namespace std; #define ll long long const int MOD = 1000037; const int jia = 1000000001; int n, x0, y0, xt, yt, ans; ll tmpx, tmpy, to[1000050]; int head[MOD + 50], nxt[1000050], num; void...