#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ll __int128
const int mod = 1e9+7;
#define forn(i,n) for(int i=0; i<n; i++)
#define readv(a,n) vector<int>a(n);forn(i,n)cin>>a[i];
#define readvv(a,n,m) vector<vector<int>> a(n,vector<int>(m));forn(i,n)forn(j,m)cin>>a[i][j];
#define all(a) a.begin(), a.end()
#define _max(x,y) x = max(x,y)
#define _min(x,y) x = min(x,y)
// #define f first
// #define s second
struct DSU{
vector<int> par;
vector<int> size;
stack<int> rb;
stack<char> tp;
stack<int> bad;
stack<pair<int,int>> edg;
int nb; int A = 0; int k;
DSU(int n){
k = n/2; par.resize(n); for(int i=0; i<n; ++i) par[i]=i;
size.resize(n,1); nb = 0;
}
int get(int p){
return par[p]==p? p: get(par[p]);
}
void unite(int a, int b){
edg.push({a,b});
if (get(a%k) == get(b%k)) {
nb++; bad.push(1);
} else bad.push(0);
a = get(a); b = get(b);
if (a==b){
rb.push(-1);
return;
}
if (size[a] > size[b]) swap(a,b);
rb.push(a);
size[b]+=size[a];
par[a] = b;
}
void rollbackHelper(){
int f = rb.top();
rb.pop();
nb -= bad.top(); bad.pop();
edg.pop();
if (f==-1) return;
size[par[f]] -= size[f];
par[f] = f;
}
void change(){
stack<pair<int,int>> edA,edB;
edB.push({edg.top().first, edg.top().second}); rollbackHelper();
int a=0, b=1; tp.pop();
while (A!=a && a!=b){
if (tp.top()=='A'){
a++; edA.push({edg.top().first, edg.top().second});
} else {
b++; edB.push({edg.top().first, edg.top().second});
}
tp.pop(); rollbackHelper();
}
while (!edB.empty()){
unite(edB.top().first, edB.top().second);
edB.pop();
tp.push('B');
}
while (!edA.empty()){
unite(edA.top().first, edA.top().second);
edA.pop();
tp.push('A');
}
}
void rollback(){
if (tp.top() == 'B') change();
int f = rb.top();
rb.pop();
nb -= bad.top(); bad.pop();
A--; tp.pop(); edg.pop();
if (f==-1) return;
size[par[f]] -= size[f];
par[f] = f;
}
};
const int N = 2e5+4;
int ans[N];
int edg[N][2];
void solve(){
int n,m,q; cin>>n>>m>>q;
for (int i=0; i<m; i++){
int a,b; cin>>a>>b; a--; b--;
edg[i][0] = a; edg[i][1] = b;
}
DSU dsu(2*n);
for (int i=0; i<=m-1; i++){
dsu.tp.push('A'); dsu.tp.push('A'); dsu.A+=2;
dsu.unite(edg[i][0], edg[i][1]+n);
dsu.unite(edg[i][0]+n, edg[i][1]);
}
int l=m-1;
for (int r = m-1; r>=0; r--){
while (l>=0 && dsu.nb){
l--;
dsu.rollback(); dsu.rollback();
}
ans[r] = l+1;
if (l==r){dsu.rollback(); dsu.rollback(); l--;}
dsu.unite(edg[r][0], edg[r][1] + n);
dsu.unite(edg[r][0] + n, edg[r][1]);
dsu.tp.push('B'); dsu.tp.push('B');
}
while (q--){
int l, r; cin>>l>>r; l--; r--;
cout<<(ans[r]<=l? "YES\n":"NO\n");
}
}
signed main(){
ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
int t = 1;
while(t--){
solve();
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
223 ms |
22224 KB |
Output is correct |
4 |
Correct |
373 ms |
25540 KB |
Output is correct |
5 |
Correct |
110 ms |
24792 KB |
Output is correct |
6 |
Correct |
94 ms |
22228 KB |
Output is correct |
7 |
Correct |
106 ms |
22224 KB |
Output is correct |
8 |
Correct |
119 ms |
21196 KB |
Output is correct |
9 |
Correct |
132 ms |
22484 KB |
Output is correct |
10 |
Correct |
207 ms |
25608 KB |
Output is correct |
11 |
Correct |
154 ms |
22308 KB |
Output is correct |
12 |
Correct |
131 ms |
24788 KB |
Output is correct |
13 |
Correct |
100 ms |
19948 KB |
Output is correct |
14 |
Correct |
160 ms |
21024 KB |
Output is correct |
15 |
Correct |
156 ms |
23504 KB |
Output is correct |
16 |
Correct |
185 ms |
25556 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
348 KB |
Output is correct |
2 |
Correct |
0 ms |
348 KB |
Output is correct |
3 |
Correct |
0 ms |
348 KB |
Output is correct |
4 |
Correct |
0 ms |
348 KB |
Output is correct |
5 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |