#include <bits/stdc++.h>
using namespace std;
int n,q;
int status[300003]; //-1:has, 0:doesn't have, other:belongs to a group where almost everyone has
int groupIndex = 0;
unordered_map<int, unordered_set<int>> grp;
void removeGroup(int grpInd) {
for(auto nr: grp.find(grpInd)->second) {
status[nr] = -1;
}
grp.erase(grpInd);
}
void joinGroups(int grp1, int grp2) {
if(grp.find(grp1)->second.size() < grp.find(grp2)->second.size()) {
int tmp = grp1;
grp1 = grp2;
grp2 = tmp;
}
auto it = grp.find(grp1); // bigger group
for(auto nr: grp.find(grp2)->second) {
status[nr] = grp1;
it->second.insert(nr);
}
grp.erase(grp2);
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
cin >> n >> q;
for(int i=0;i<q;i++) {
char op;
int nr1;
cin >> op >> nr1;
if(op == '+') {
int nr2;
cin >> nr2;
int g1 = status[nr1];
int g2 = status[nr2];
if(nr1==nr2) {
if(g1 > 0) {
removeGroup(g1);
} else if(g1 == 0) {
status[nr1] = -1;
} else {
cout << "incorrect data1";
return 0;
}
} else if(g1 > 0) {
if(g2 > 0) {
if(g1 == g2) {
removeGroup(g1);
} else {
joinGroups(g1, g2);
}
} else if(g2 == 0) {
grp.find(g1)->second.insert(nr2);
status[nr2] = g1;
} else if(g2 == -1) {
removeGroup(g1);
}
} else if(g1 == 0) {
if(g2 > 0) {
grp.find(g2)->second.insert(nr1);
status[nr1] = g2;
} else if(g2 == 0) {
// create common group
groupIndex++;
status[nr1] = groupIndex;
status[nr2] = groupIndex;
unordered_set<int> s;
s.insert(nr1);
s.insert(nr2);
grp[groupIndex] = s;
} else if(g2 == -1) {
status[nr1] = -1;
}
} else if(g1 == -1) {
if(g2 > 0) {
removeGroup(g2);
} else if(g2 == 0) {
status[nr2] = -1;
} else if(g2 == -1) {
cout << "incorrect data2";
return 0;
}
}
} else if(op == '?') {
int g = status[nr1];
if(g == -1) cout << '1';
else if(g == 0) cout << '0';
else cout << '?';
} else if(op == '-') {
int g = status[nr1];
if(g > 0) {
auto it = grp.find(g);
it->second.erase(nr1);
if(it->second.size()==1) {
status[*(it->second.begin())] = 0;
grp.erase(g);
}
}
status[nr1] = 0;
}
/*cout << endl << "grp ---------------- ";
for(auto p: grp) {
cout << p.first << ": ";
for(auto nr: p.second) {
cout << nr << ",";
}
cout << endl;
}
for(int i=1;i<=n;i++) {
cout << status[i];
}
cout << endl;*/
}
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 | #include <bits/stdc++.h> using namespace std; int n,q; int status[300003]; //-1:has, 0:doesn't have, other:belongs to a group where almost everyone has int groupIndex = 0; unordered_map<int, unordered_set<int>> grp; void removeGroup(int grpInd) { for(auto nr: grp.find(grpInd)->second) { status[nr] = -1; } grp.erase(grpInd); } void joinGroups(int grp1, int grp2) { if(grp.find(grp1)->second.size() < grp.find(grp2)->second.size()) { int tmp = grp1; grp1 = grp2; grp2 = tmp; } auto it = grp.find(grp1); // bigger group for(auto nr: grp.find(grp2)->second) { status[nr] = grp1; it->second.insert(nr); } grp.erase(grp2); } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n >> q; for(int i=0;i<q;i++) { char op; int nr1; cin >> op >> nr1; if(op == '+') { int nr2; cin >> nr2; int g1 = status[nr1]; int g2 = status[nr2]; if(nr1==nr2) { if(g1 > 0) { removeGroup(g1); } else if(g1 == 0) { status[nr1] = -1; } else { cout << "incorrect data1"; return 0; } } else if(g1 > 0) { if(g2 > 0) { if(g1 == g2) { removeGroup(g1); } else { joinGroups(g1, g2); } } else if(g2 == 0) { grp.find(g1)->second.insert(nr2); status[nr2] = g1; } else if(g2 == -1) { removeGroup(g1); } } else if(g1 == 0) { if(g2 > 0) { grp.find(g2)->second.insert(nr1); status[nr1] = g2; } else if(g2 == 0) { // create common group groupIndex++; status[nr1] = groupIndex; status[nr2] = groupIndex; unordered_set<int> s; s.insert(nr1); s.insert(nr2); grp[groupIndex] = s; } else if(g2 == -1) { status[nr1] = -1; } } else if(g1 == -1) { if(g2 > 0) { removeGroup(g2); } else if(g2 == 0) { status[nr2] = -1; } else if(g2 == -1) { cout << "incorrect data2"; return 0; } } } else if(op == '?') { int g = status[nr1]; if(g == -1) cout << '1'; else if(g == 0) cout << '0'; else cout << '?'; } else if(op == '-') { int g = status[nr1]; if(g > 0) { auto it = grp.find(g); it->second.erase(nr1); if(it->second.size()==1) { status[*(it->second.begin())] = 0; grp.erase(g); } } status[nr1] = 0; } /*cout << endl << "grp ---------------- "; for(auto p: grp) { cout << p.first << ": "; for(auto nr: p.second) { cout << nr << ","; } cout << endl; } for(int i=1;i<=n;i++) { cout << status[i]; } cout << endl;*/ } return 0; } |
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