#include <bits/stdc++.h>
using namespace std;
// short forms //
#define nl "\n"
#define pb push_back
#define f first
#define s second
#define ll long long int
#define ld long double
#define mp make_pair
#define all(x) x.begin(), x.end()
// debug //
#define pv(x) for(auto k : x){cout << k << " ";} cout << nl;
#define pp(x) cout << x.f << " " << x.s << nl;
#define bv(x) if (x) cout << "true"; else cout << "false";
#define gp(x, y) x << " " << y
// loop //
#define FOR(i, a, b) for(ll i = a; i <=b; i++)
// pair //
typedef pair<ll, ll> pl;
// vector //
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pl> vp;
// constants //
const ll INF = 1e17;
const ll mod = 1e9 + 7;
const ll S = 1e5 + 5;
ll n, siz[S], link[S], eof[S];
ll find(ll a){
ll st = a;
while(a != link[a]) a = link[a];
//path compression
while(st != link[st]){
ll tmp = link[st];
link[st] = a;
st = tmp;
}
return a;
}
bool unite(ll a, ll b){
a = find(a);
b = find(b);
if (a == b) return 0;
// union by size
if (siz[a] < siz[b]) swap(a, b);
siz[a] += siz[b];
link[b] = a;
}
void set_same(ll a, ll b){
/*
1) unite the friends
2) unite the enemies of the friends
3) copy the link
*/
a = find(a);
b = find(b);
if (siz[a] < siz[b]) swap(a, b);
// a is the bigger set
unite(a, b);
if (eof[a] != -1 && eof[b] != -1)
unite(eof[a], eof[b]);
if (eof[a] == -1)
eof[a] = eof[b];
}
void set_op(ll c1, ll c2){
/*
Most importantly, this is symmetric
so the enemy of c1 is united with rep of c1 and vice versa
*/
ll set1 = find(c1);
ll set2 = find(c2);
ll e = eof[set1];
if (e == -1)
eof[set1] = c2;
else
unite(e, c2);
e = eof[set2];
if (e == -1)
eof[set2] = c1;
else
unite(e, c1);
}
void query(ll a, ll b){
a = find(a);
b = find(b);
if (a == b){
cout << 'R' << nl;
return; // repel
}
if (find(eof[a]) == b){
cout << 'A' << nl;
return; // attract
}
if (eof[a] == -1){
cout << '?' << nl;
return;
}
}
void solve(){
FOR(i, 0, S-1){
link[i] = i;
siz[i] = 1;
eof[i] = -1;
}
ll q;
cin >> n >> q;
while(q--){
char t;
ll a, b;
cin >> t;
cin >> a >> b;
if (t == 'A'){
set_op(a, b);
}else if (t == 'R'){
set_same(a, b);
}else{
// cout << "for " << gp(a, b) << nl;
// cout << find(a) << ' ' << find(b) << nl;
query(a, b);
}
}
}
int main(){
ios::sync_with_stdio(0);
cin.tie(0);
ll t = 1;
//cin >> t;
while(t--){
solve();
}
return 0;
}
Compilation message
charges.cpp: In function 'bool unite(long long int, long long int)':
charges.cpp:58:13: warning: control reaches end of non-void function [-Wreturn-type]
58 | link[b] = a;
| ~~~~~~~~^~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
6 ms |
5204 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
4 ms |
5204 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
4 ms |
5204 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
4 ms |
5204 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
6 ms |
5204 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
6 ms |
5204 KB |
Execution killed with signal 11 |
| 2 |
Halted |
0 ms |
0 KB |
- |
