#include <iostream>
#include <unordered_set>
#include <vector>
using namespace std;
struct Data {
unordered_set<int> citizens;
char type;
};
int main() {
ios::sync_with_stdio(false);
std::cin.tie(nullptr);
int n, q;
cin >> n >> q;
vector<Data *> arr;
arr.resize(n + 1, nullptr);
for (int i = 0; i < q; ++i) {
char c;
cin >> c;
switch (c) {
case '+': {
int a, b;
cin >> a >> b;
if (arr[a] != nullptr && arr[b] != nullptr) {
if (arr[a] == arr[b]) {
arr[a]->type = 'c';
} else {
Data *bigger = arr[a]->citizens.size() > arr[b]->citizens.size() ? arr[a] : arr[b];
Data *smaller = bigger == arr[a] ? arr[b] : arr[a];
bigger->type = arr[a]->type == 'c' || arr[b]->type == 'c' ? 'c' : 't';
for (int citizen : smaller->citizens) {
arr[citizen] = bigger;
}
bigger->citizens.insert(begin(smaller->citizens), end(smaller->citizens));
delete smaller;
}
} else if (arr[a] != nullptr) {
arr[b] = arr[a];
arr[b]->citizens.insert(b);
} else if (arr[b] != nullptr) {
arr[a] = arr[b];
arr[a]->citizens.insert(a);
} else {
arr[a] = new Data{};
arr[b] = arr[a];
arr[a]->citizens.insert(a);
arr[b]->citizens.insert(b);
arr[a]->type = a == b ? 'c' : 't';
}
break;
}
case '-': {
int c;
cin >> c;
if (arr[c]->citizens.size() == 1) {
delete arr[c];
arr[c] = nullptr;
} else if (arr[c]->citizens.size() == 2) {
if (arr[c]->type == 'c') {
arr[c]->citizens.erase(c);
arr[c] = nullptr;
} else {
auto ptr = arr[c];
arr[*ptr->citizens.begin()] = nullptr;
arr[*++ptr->citizens.begin()] = nullptr;
delete ptr;
}
} else {
arr[c]->citizens.erase(c);
arr[c] = nullptr;
}
break;
}
case '?': {
int d;
cin >> d;
if (!arr[d]) {
cout << '0';
} else if (arr[d]->type == 'c') {
cout << '1';
} else {
cout << '?';
}
break;
}
}
}
cout << endl;
}
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 | #include <iostream> #include <unordered_set> #include <vector> using namespace std; struct Data { unordered_set<int> citizens; char type; }; int main() { ios::sync_with_stdio(false); std::cin.tie(nullptr); int n, q; cin >> n >> q; vector<Data *> arr; arr.resize(n + 1, nullptr); for (int i = 0; i < q; ++i) { char c; cin >> c; switch (c) { case '+': { int a, b; cin >> a >> b; if (arr[a] != nullptr && arr[b] != nullptr) { if (arr[a] == arr[b]) { arr[a]->type = 'c'; } else { Data *bigger = arr[a]->citizens.size() > arr[b]->citizens.size() ? arr[a] : arr[b]; Data *smaller = bigger == arr[a] ? arr[b] : arr[a]; bigger->type = arr[a]->type == 'c' || arr[b]->type == 'c' ? 'c' : 't'; for (int citizen : smaller->citizens) { arr[citizen] = bigger; } bigger->citizens.insert(begin(smaller->citizens), end(smaller->citizens)); delete smaller; } } else if (arr[a] != nullptr) { arr[b] = arr[a]; arr[b]->citizens.insert(b); } else if (arr[b] != nullptr) { arr[a] = arr[b]; arr[a]->citizens.insert(a); } else { arr[a] = new Data{}; arr[b] = arr[a]; arr[a]->citizens.insert(a); arr[b]->citizens.insert(b); arr[a]->type = a == b ? 'c' : 't'; } break; } case '-': { int c; cin >> c; if (arr[c]->citizens.size() == 1) { delete arr[c]; arr[c] = nullptr; } else if (arr[c]->citizens.size() == 2) { if (arr[c]->type == 'c') { arr[c]->citizens.erase(c); arr[c] = nullptr; } else { auto ptr = arr[c]; arr[*ptr->citizens.begin()] = nullptr; arr[*++ptr->citizens.begin()] = nullptr; delete ptr; } } else { arr[c]->citizens.erase(c); arr[c] = nullptr; } break; } case '?': { int d; cin >> d; if (!arr[d]) { cout << '0'; } else if (arr[d]->type == 'c') { cout << '1'; } else { cout << '?'; } break; } } } cout << endl; } |
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