#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2e5 + 5, MOD = 998244353;
int p[N],sz[N],n,m,q,d[N];
void reset(){
for(int i = 1;i <= n;i++){
sz[i] = 1;
p[i] = i;
d[i] = 0;
}
}
pair<int, int> get(int v) {
if(p[v] == v){
return {v,0};
}
pair<int,int> x = get(p[v]);
return {x.first,d[v]+x.second};
}
vector<array<int,5>> st;
bool merge(int a,int b){
pair<int,int> x = get(a),y = get(b);
if(sz[x.first] < sz[y.first]){
swap(x,y);
}
a = x.first;
b = y.first;
if(a == b){
if(x.second % 2 == y.second % 2){
st.push_back({a,b,-1,1,0});
return true;
}
st.push_back({a,b,-1,0,0});
return false;
}
st.push_back({a,b,sz[a],p[b],d[b]});
p[b] = a;
sz[a] += sz[b];
d[b] = (x.second % 2 == y.second % 2);
return false;
}
int rr[N],cur_col = 0;
void roll_back(){
auto dd = st.back();
st.pop_back();
if(dd[2] == -1){
cur_col -= dd[3];
return;
}
sz[dd[0]] = dd[2];
p[dd[1]] = dd[3];
d[dd[1]] = dd[4];
}
int check_rb(){
auto dd = st.back();
if(dd[2] != -1) return 0;
return dd[3];
}
int check_merge(int a,int b){
pair<int,int> x = get(a),y = get(b);
if(x.first != x.second) return 0;
return (x.second % 2 == y.second % 2);
}
int x[N],y[N];
vector<pair<int,int>> qr[N];
vector<int> ids[N];
bool ans[N];
void precalc(){
reset();
for(int i = m;i >= 1;i--){
cur_col += merge(x[i],y[i]);
if(cur_col){
rr[0] = i;
break;
}
}
if(rr[0] == 0){
return;
}
// cout << 0 << ' ' << rr[0] << '\n';
for(int i = 1;i <= m;i++){
rr[i] = rr[i - 1];
cur_col += check_merge(x[i],y[i]);
// cout << cur_col << '\n';
while(rr[i] <= m && cur_col - check_rb() >= 1){
roll_back();
rr[i]++;
}
merge(x[i],y[i]);
// cout << i << ' ' << rr[i] << '\n';
}
}
void test(){
cin >> n >> m >> q;
for(int i = 1;i <= m;i++){
cin >> x[i] >> y[i];
}
precalc();
for(int i = 1;i <=q;i++){
int l,r;
cin >> l >> r;
cout << (rr[l] >= r ? "YES\n":"NO\n");
}
}
int main(){
ios_base::sync_with_stdio(false);cin.tie(0);
int T = 1;
// cin >> T;
while(T--){
test();
}
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
12636 KB |
Output is correct |
2 |
Correct |
2 ms |
12636 KB |
Output is correct |
3 |
Correct |
2 ms |
12636 KB |
Output is correct |
4 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
12636 KB |
Output is correct |
2 |
Correct |
2 ms |
12636 KB |
Output is correct |
3 |
Correct |
2 ms |
12636 KB |
Output is correct |
4 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
12636 KB |
Output is correct |
2 |
Correct |
2 ms |
12636 KB |
Output is correct |
3 |
Incorrect |
60 ms |
19072 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
12636 KB |
Output is correct |
2 |
Correct |
2 ms |
12636 KB |
Output is correct |
3 |
Correct |
2 ms |
12636 KB |
Output is correct |
4 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
12636 KB |
Output is correct |
2 |
Correct |
2 ms |
12636 KB |
Output is correct |
3 |
Correct |
2 ms |
12636 KB |
Output is correct |
4 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
12636 KB |
Output is correct |
2 |
Correct |
2 ms |
12636 KB |
Output is correct |
3 |
Correct |
2 ms |
12636 KB |
Output is correct |
4 |
Incorrect |
2 ms |
12636 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |