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
156
157
158
159
160
161
162
163
164
| //
// main.cpp
// HDU3234
//
// Created by zhangmin chen on 2019/7/10.
// Copyright © 2019 zhangmin chen. All rights reserved.
//
using namespace std;
typedef long long llong;
typedef set<int>::iterator ssii;
const int maxn = 20000 + 10;
const int maxl = 40000 + 10;
int n, q;
int pa[maxn], d[maxn];
int vis[maxn];
int line[maxl][3];
int data[maxn];
void initSet() {
Set(line, 0);
Set(data, 0);
_for(i, 0, maxn) {
pa[i] = i;
d[i] = 0;
}
}
int findSet(int x) {
if(x == pa[x]) return x;
else {
int root = findSet(pa[x]);
d[x] ^= d[pa[x]];
return pa[x] = root;
}
}
bool combine(int p, int q, int v) {
int rootp = findSet(p);
int rootq = findSet(q);
if(rootp == rootq) return (d[p] ^ d[q]) == v;
//debug(nil);
// union rootp and rootq, d[p] ^ d[q] = v
// pa[rootp] = rootq
if(rootp == n) swap(rootp, rootq);
pa[rootp] = rootq;
d[rootp] = (d[p] ^ d[q] ^ v);
return true;
}
int query(const int *data, int k) {
int ans = 0;
Set(vis, 0);
_for(i, 0, k) {
// d[data[i]]
if(vis[i]) continue;
int cnt = 0, root = findSet(data[i]);
_for(j, i, k) {
if(!vis[j] && root == findSet(data[j])) {
vis[j] = 1;
cnt++;
ans ^= d[data[j]];
}
}
if(root != n && cnt % 2 == 1) return -1;
}
return ans;
}
int main() {
freopen("input.txt", "r", stdin);
int cnt = 0;
while (scanf("%d%d", &n, &q) && (n + q)) {
initSet();
printf("Case %d:\n", ++cnt);
//debug(n);
int ic = 0;
bool bug = 0;
_for(i, 0, q) {
string str;
cin >> str;
if(str[0] == 'I') {
//
ic++;
int sz = 0;
while(cin >> line[i][sz++]) if(getchar() == '\n') break;
if(bug) continue;
int p = 0, q = 0, v = 0;
if(sz == 2) {
// I p v, data[0] = p, data[1] = v
p = line[i][0]; v = line[i][1];
q = n;
}
else if(sz == 3) {
// I p q v
p = line[i][0]; q = line[i][1]; v = line[i][2];
}
if(!combine(p, q, v)) {
printf("The first %d facts are conflicting.\n", ic);
bug = 1;
}
}
else if(str[0] == 'Q') {
// k p1 p2 ... pk
int k;
scanf("%d", &k);
// _for(i, 0, data.size()) cout << data[i] << " ";
// cout << endl;
_for(i, 0, k) scanf("%d", &data[i]);
if(bug) continue;
int res = query(data, k);
if(res == -1) printf("I don't know.\n");
else printf("%d\n", res);
}
// _for(i, 0, data.size()) cout << data[i] << " ";
// cout << endl;
}
puts("");
}
}
|
微信
支付宝
