#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define f first
#define s second
vector<set<long> > adjs; // note that will have to findSet each of these.
class UFDS
{
public:
vector<long> parent, sizes;
long num_sets;
UFDS(long n) {
for (long i=0; i<n; i++) {
parent.push_back(i);
}
for (long i=0; i<n; i++) {
sizes.push_back(1);
}
num_sets = n;
}
long findSet(long i) {
if (parent[i] == i) return i;
vector<long> elems; // path compression
while (parent[i] != i) {
elems.push_back(i);
i = parent[i];
}
for (long idx=0; idx<elems.size(); idx++) {
parent[elems[i]] = i;
}
return i;
}
void unionSets(long i, long j) {
//cout << "UNION " << i << ' ' << j << ": ";
i = findSet(i);
j = findSet(j);
//cout << i << ' ' << j << "; ";
if (i==j) return;
if (sizes[i] < sizes[j]) swap(i, j); // so i >= j in size, not rlly depth but.
parent[j] = i; // set parent
//cout << sizes[i] << ' ' << sizes[j] << ": ";
sizes[i] += sizes[j]; // update size
//cout << sizes[i] << ' ' << sizes[j] << "; ";
// union the adjs
for (auto it = adjs[j].begin(); it != adjs[j].end(); it++) {
adjs[i].insert(*it);
}
adjs[j].clear();
// update number of sets
num_sets --;
// done :)
}
//long getSize(long s) return sizes[s];
};
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
// modifier ufds
// store unordered set of neighbours of each edge and when union, combine them.
long n, m;
cin >> n >> m;
for (long idx=0; idx<n; idx++) adjs.push_back(set<long>());
long i, j;
char t;
UFDS ufds(n);
for (long idx=0; idx<m; idx++) {
cin >> i >> j >> t;
if (t=='A') {
// add to adjs
i = ufds.findSet(i-1);
j = ufds.findSet(j-1);
adjs[i].insert(j);
adjs[j].insert(i);
} else {
// union the sets
ufds.unionSets(i-1, j-1);
}
}
// ufds done:)
// check.
/*cout << "UFDS DEBUG: \n";
cout << "PARENT: ";
for (long i=0; i<n; i++) cout << ufds.parent[i] << ' ';
cout << endl;
cout << "SIZE: ";
for (long i=0; i<n; i++) cout << ufds.sizes[i] << ' ';
cout << endl;
cout << "ADJ: " << endl;
for (long i=0; i<n; i++) {
cout << i << ": ";
for (auto it=adjs[i].begin(); it!=adjs[i].end(); it++) {
cout << *it << ' ' ;
}
cout << endl;
}
cout << endl << endl;*/
// get size of each component's adjs (rmbring to remove duplicates)
long res=0;
set<long> s;
for (long i=0; i<n; i++) {
//cout << i << ": ";
for (auto it=adjs[i].begin(); it!=adjs[i].end(); it++) {
s.insert(ufds.findSet(*it)); // add
//cout << ufds.findSet(*it) << ' ';
}
//cout << endl;
if (s.size() == ufds.num_sets-1) {
//cout << "COUNTED: " << i << endl;
res += ufds.sizes[i];
}
s.clear(); // :)
}
cout << res << '\n';
return 0;
}
Compilation message
menesinis_bilietas.cpp: In member function 'long int UFDS::findSet(long int)':
menesinis_bilietas.cpp:31:29: warning: comparison of integer expressions of different signedness: 'long int' and 'std::vector<long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
31 | for (long idx=0; idx<elems.size(); idx++) {
| ~~~^~~~~~~~~~~~~
menesinis_bilietas.cpp: In function 'int main()':
menesinis_bilietas.cpp:131:22: warning: comparison of integer expressions of different signedness: 'std::set<long int>::size_type' {aka 'long unsigned int'} and 'long int' [-Wsign-compare]
131 | if (s.size() == ufds.num_sets-1) {
| ^
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
46 ms |
50940 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
21 ms |
34236 KB |
Output is correct |
2 |
Correct |
0 ms |
344 KB |
Output is correct |
3 |
Correct |
1 ms |
348 KB |
Output is correct |
4 |
Correct |
3 ms |
1116 KB |
Output is correct |
5 |
Correct |
1 ms |
1368 KB |
Output is correct |
6 |
Correct |
543 ms |
37220 KB |
Output is correct |
7 |
Correct |
733 ms |
83340 KB |
Output is correct |
8 |
Correct |
9 ms |
3284 KB |
Output is correct |
9 |
Correct |
15 ms |
4820 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
344 KB |
Output is correct |
2 |
Correct |
1 ms |
348 KB |
Output is correct |
3 |
Correct |
3 ms |
1116 KB |
Output is correct |
4 |
Runtime error |
1 ms |
600 KB |
Execution killed with signal 11 |
5 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
1 ms |
600 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
1 ms |
600 KB |
Execution killed with signal 11 |
2 |
Halted |
0 ms |
0 KB |
- |