Codeforces 1144D Deduction Queries 並查集
阿新 • • 發佈:2019-05-16
cin nbsp ref size bits its \n sca add
Deduction Queries
用並查集維護前綴的關系, 在同一個聯通塊內兩兩之間的異或值都是已知的。
每個點再維護一個和它當前父親的異或值, 壓縮路徑的時候更新一下就好了。
#include<bits/stdc++.h> #define LL long long #define LD long double #define ull unsigned long long #define fi first #define se second #define mk make_pair #define PLL pair<LL, LL> #definePLI pair<LL, int> #define PII pair<int, int> #define SZ(x) ((int)x.size()) #define ALL(x) (x).begin(), (x).end() #define fio ios::sync_with_stdio(false); cin.tie(0); using namespace std; const int N = 5e5 + 7; const int inf = 0x3f3f3f3f; const LL INF = 0x3f3f3f3f3f3f3f3f; constint mod = 1e9 + 7; const double eps = 1e-8; const double PI = acos(-1); template<class T, class S> inline void add(T& a, S b) {a += b; if(a >= mod) a -= mod;} template<class T, class S> inline void sub(T& a, S b) {a -= b; if(a < 0) a += mod;} template<class T, classS> inline bool chkmax(T& a, S b) {return a < b ? a = b, true : false;} template<class T, class S> inline bool chkmin(T& a, S b) {return a > b ? a = b, true : false;} int q, tot; map<int, int> Map; int xorWithFa[N]; int fa[N]; int getRoot(int x) { if(x == fa[x]) return x; int preFa = fa[x]; int nowFa = getRoot(fa[x]); xorWithFa[x] ^= xorWithFa[preFa]; return fa[x] = nowFa; } int main() { for(int i = 1; i < N; i++) fa[i] = i; scanf("%d", &q); int ans = 0; while(q--) { int op; scanf("%d", &op); if(op == 1) { int l, r, x; scanf("%d%d%d", &l, &r, &x); l ^= ans; r ^= ans; x ^= ans; if(l > r) swap(l, r); l--; if(Map.find(l) == Map.end()) Map[l] = ++tot; if(Map.find(r) == Map.end()) Map[r] = ++tot; l = Map[l]; r = Map[r]; int fal = getRoot(l); int far = getRoot(r); if(fal != far) { int xor1 = xorWithFa[l]; int xor2 = xorWithFa[r]; fa[far] = fal; xorWithFa[far] = xor1 ^ xor2 ^ x; } } else { int l, r; scanf("%d%d", &l, &r); l ^= ans; r ^= ans; if(l > r) swap(l, r); l--; if(Map.find(l) == Map.end() || Map.find(r) == Map.end()) { puts("-1"); ans = 1; } else { l = Map[l]; r = Map[r]; int fal = getRoot(l); int far = getRoot(r); if(fal != far) { puts("-1"); ans = 1; } else { ans = xorWithFa[l] ^ xorWithFa[r]; printf("%d\n", ans); } } } } return 0; } /* */
Codeforces 1144D Deduction Queries 並查集