1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
| #include <bits/stdc++.h>
using namespace std;
#define ll long long
vector<vector<int>> adj;
int N, Q;
vector<int> st, ed;
vector<int> enjoy;
vector<int> depth;
#ifdef SIMPLE_LCA
vector<int> parent;
#else
vector<vector<int>> up(2e5 + 1, vector<int> (20));
#endif
int T = 1;
class BIT {
vector<long long> tree;
public:
void init(int x) {
tree.resize(x);
}
void update(ll i, ll x) {
while (i < tree.size()) {
tree[i] ^= x;
i = i + (i & (-i));
}
}
ll query(ll i) {
ll ans = 0;
while (i > 0) {
ans ^= tree[i];
i = i - (i & (-i));
}
return ans;
}
};
// euler tour
void dfs(int c, int p) {
st[c] = T++;
depth[c] = depth[p] + 1;
#ifdef SIMPLE_LCA
parent[c] = p;
#else
up[c][0] = p;
for (int i = 1; i < 20; i++) {
up[c][i] = up[up[c][i-1]][i-1];
}
#endif
for (int n : adj[c]) {
if (n != p) {
dfs(n, c);
}
}
ed[c] = T - 1;
}
#ifdef SIMPLE_LCA
int lca(int a, int b) {
// lca
if (depth[a] > depth[b]) {
swap (a, b);
}
while (depth[a] < depth[b]) {
b = parent[b];
}
while (a != b) {
a = parent[a];
b = parent[b];
}
return a;
}
#else
int lca(int a, int b) {
if (depth[a] > depth[b]) {
swap (a, b);
}
// binary jumping
int d = depth[b] - depth[a];
for (int i = 0; i < 20; i++) {
if((d >> i) & 1) {
b = up[b][i];
}
}
if(a == b) return a;
//lca using binary jumping
for (int i = 19; i >= 0; i--) {
int ap = up[a][i];
int bp = up[b][i];
if(ap != bp) a = ap, b = bp;
}
return up[a][0];
}
#endif
int main() {
ifstream cin("cowland.in");
ofstream cout("cowland.out");
cin >> N >> Q;
cin >> N >> Q;
enjoy.resize(N + 1);
adj.resize(N + 1);
st.resize(N + 1); ed.resize(N + 1);
#ifdef SIMPLE_LCA
parent.resize(N + 1);
#endif
depth.resize(N + 1);
depth[0] = 0;
BIT tree;
tree.init(N + 1);
for (int i = 1; i < N + 1; i++) {
cin >> enjoy[i];
}
for (int i = 0; i < N - 1; i++) {
int a, b; cin >> a >> b;
adj[a].push_back(b);
adj[b].push_back(a);
}
depth[0] = -1;
dfs(1, 0);
for (int i = 1; i < N + 1; i++) {
tree.update(st[i], enjoy[i]);
tree.update(ed[i] + 1, enjoy[i]);
}
for (int i = 0; i < Q; i++) {
int t;
cin >> t;
if (t == 1) {
int a, b;
cin >> a >> b;
tree.update(st[a], enjoy[a]);
tree.update(ed[a] + 1, enjoy[a]);
tree.update(st[a], b);
tree.update(ed[a] + 1, b);
enjoy[a] = b;
}
else {
int a, b;
cin >> a >> b;
int pathsuma = tree.query(st[a]);
int pathsumb = tree.query(st[b]);
a = lca(a, b);
int ans = pathsuma ^ pathsumb ^ enjoy[a];
cout << ans << endl;
}
}
}
|