#include<bits/stdc++.h> using namespace std; enum State { ZERO, ONE, UNKNOWN }; ostream& operator<< (ostream& out, const State& s) { if(s == ZERO) out << "0"; else if(s == ONE) out << "1"; else out << "?"; return out; } struct FU { vector<int> rep; vector<vector<int>> group; vector<int> cnt; FU(int n): rep(n), group(n), cnt(n, 1) { for(int i=0;i<n;i++) rep[i] = i, group[i] = {i}; } int find(int x) { return (rep[x] == x ? x : rep[x] = find(rep[x])); } bool merge(int a, int b) { a = find(a), b = find(b); if(a == b) return false; if(group[a].size() < group[b].size()) swap(a, b); rep[b] = a; cnt[a] += cnt[b]; for(int i : group[b]) group[a].push_back(i); group[b].clear(); return true; } void reset(int x) { rep[x] = x; group[x] = {x}; } }; int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); int n,q; cin >> n >> q; FU f(n+q); vector<int> rep(n+q); int cnt = n; vector<vector<int>> id(n); for(int i=0;i<n;i++) id[i] = {i}, rep[i] = i; vector<State> result(n+q, State::ZERO); auto reset = [&](const vector<int>& A, const State& s) { for(int i : A) { auto t = (result[i] == ZERO ? ZERO : s); result[i] = t; f.reset(i); f.cnt[f.find(i)] = (t == ZERO ? 1 : 0); } }; auto touch = [&](int x) { if(result[x] == ZERO) result[x] = UNKNOWN, f.cnt[f.find(x)]--; }; for(int it=1;it<=q;it++) { char t; cin >> t; if(t == '?') { int a; cin >> a, a--; cout << result[id[a].back()]; } else if(t == '+') { int a, b; cin >> a >> b, a--, b--; a = id[a].back(), b = id[b].back(); if(f.merge(a, b) && result[a] != ONE && result[b] != ONE) { touch(a), touch(b); } else { touch(a), touch(b); auto A = f.group[f.find(a)]; auto B = f.group[f.find(b)]; A.insert(A.end(), B.begin(), B.end()); reset(A, ONE); } } else { int a; cin >> a, a--; a = id[a].back(); if(result[a] == ZERO) continue; result[a] = ZERO; int r = f.find(a); f.cnt[r]++; if(f.cnt[r]+1 == f.group[r].size()) reset(f.group[r], ZERO); else { int x = cnt++; id[rep[a]].push_back(x); rep[x] = rep[a]; } } } cout << "\n"; return 0; }
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 | #include<bits/stdc++.h> using namespace std; enum State { ZERO, ONE, UNKNOWN }; ostream& operator<< (ostream& out, const State& s) { if(s == ZERO) out << "0"; else if(s == ONE) out << "1"; else out << "?"; return out; } struct FU { vector<int> rep; vector<vector<int>> group; vector<int> cnt; FU(int n): rep(n), group(n), cnt(n, 1) { for(int i=0;i<n;i++) rep[i] = i, group[i] = {i}; } int find(int x) { return (rep[x] == x ? x : rep[x] = find(rep[x])); } bool merge(int a, int b) { a = find(a), b = find(b); if(a == b) return false; if(group[a].size() < group[b].size()) swap(a, b); rep[b] = a; cnt[a] += cnt[b]; for(int i : group[b]) group[a].push_back(i); group[b].clear(); return true; } void reset(int x) { rep[x] = x; group[x] = {x}; } }; int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); int n,q; cin >> n >> q; FU f(n+q); vector<int> rep(n+q); int cnt = n; vector<vector<int>> id(n); for(int i=0;i<n;i++) id[i] = {i}, rep[i] = i; vector<State> result(n+q, State::ZERO); auto reset = [&](const vector<int>& A, const State& s) { for(int i : A) { auto t = (result[i] == ZERO ? ZERO : s); result[i] = t; f.reset(i); f.cnt[f.find(i)] = (t == ZERO ? 1 : 0); } }; auto touch = [&](int x) { if(result[x] == ZERO) result[x] = UNKNOWN, f.cnt[f.find(x)]--; }; for(int it=1;it<=q;it++) { char t; cin >> t; if(t == '?') { int a; cin >> a, a--; cout << result[id[a].back()]; } else if(t == '+') { int a, b; cin >> a >> b, a--, b--; a = id[a].back(), b = id[b].back(); if(f.merge(a, b) && result[a] != ONE && result[b] != ONE) { touch(a), touch(b); } else { touch(a), touch(b); auto A = f.group[f.find(a)]; auto B = f.group[f.find(b)]; A.insert(A.end(), B.begin(), B.end()); reset(A, ONE); } } else { int a; cin >> a, a--; a = id[a].back(); if(result[a] == ZERO) continue; result[a] = ZERO; int r = f.find(a); f.cnt[r]++; if(f.cnt[r]+1 == f.group[r].size()) reset(f.group[r], ZERO); else { int x = cnt++; id[rep[a]].push_back(x); rep[x] = rep[a]; } } } cout << "\n"; return 0; } |