#include<bits/stdc++.h>
#define ll long long
#define pii pair<int,ll>
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(),x.end()
using namespace std;
const int mxn=4e5+5;
vector<pii>edge;
int pr[mxn]{0},m,n;
int dp[mxn]{0};
int sz[mxn]{0};
stack<pii>st;
void rollback(int x){
while(st.size()>x){
pr[st.top().f]=st.top().f;
sz[st.top().s]-=sz[st.top().f];
st.pop();
}
}
int get(int r){
return pr[r]==r?r:get(pr[r]);
}
void uni(int a,int b){
a=get(a),b=get(b);
if(a==b)return;
if(sz[a]>sz[b])swap(a,b);
pr[a]=b;sz[b]+=sz[a];
st.push({a,b});
}
void solve(int l1,int r1,int l2,int r2,bool ok){
if(l1>r1)return;
if(ok){
for(int i=l1;i<=r1;i++)dp[i]=r2;
return;
}
int md=(l1+r1)>>1,md2=-1;
int pv1=st.size();
bool ok2=ok;
for(int i=l1;i<=md-1;i++){
uni(edge[i-1].f,edge[i-1].s+n);
uni(edge[i-1].f+n,edge[i-1].s);
if(get(edge[i-1].f)==get(edge[i-1].f+n))ok2|=1;
}int pv2=st.size();
for(int i=r2;i>=max(l2,md);i--){
uni(edge[i-1].f,edge[i-1].s+n);
uni(edge[i-1].f+n,edge[i-1].s);
if(get(edge[i-1].f)==get(edge[i-1].f+n)){md2=i-1;break;}
}if(md2==-1)md2=md-1;
dp[md]=md2;rollback(pv2);uni(edge[md-1].f,edge[md-1].s+n);
uni(edge[md-1].f+n,edge[md-1].s);
if(get(edge[md-1].f)==get(edge[md-1].f+n))ok2|=1;
solve(md+1,r1,md2,r2,ok2);
rollback(pv1);ok2=ok;
for(int i=r2;i>=md2+1;i--){
uni(edge[i-1].f,edge[i-1].s+n);
uni(edge[i-1].f+n,edge[i-1].s);
if(get(edge[i-1].f)==get(edge[i-1].f+n))ok2|=1;
}
solve(l1,md-1,l2,md2,ok2);rollback(pv1);
}
int main(){
ios_base::sync_with_stdio(0);cin.tie(0);
int q;cin>>n>>m>>q;iota(pr,pr+2*n+1,0);
for(int i=1;i<=n;i++)sz[i]=1;
for(int i=0;i<m;i++){
int u,v;cin>>u>>v;
edge.pb({u,v});
}solve(1,m,1,m,0);
while(q--){
int l,r;cin>>l>>r;
cout<<(r<=dp[l]?"YES\n":"NO\n");
}
}
Compilation message
Joker.cpp: In function 'void rollback(int)':
Joker.cpp:16:20: warning: comparison of integer expressions of different signedness: 'std::stack<std::pair<int, long long int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
16 | while(st.size()>x){
| ~~~~~~~~~^~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4440 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
0 ms |
4444 KB |
Output is correct |
4 |
Correct |
0 ms |
4444 KB |
Output is correct |
5 |
Correct |
0 ms |
4444 KB |
Output is correct |
6 |
Incorrect |
0 ms |
4444 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4440 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
0 ms |
4444 KB |
Output is correct |
4 |
Correct |
0 ms |
4444 KB |
Output is correct |
5 |
Correct |
0 ms |
4444 KB |
Output is correct |
6 |
Incorrect |
0 ms |
4444 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4440 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
110 ms |
11556 KB |
Output is correct |
4 |
Correct |
222 ms |
16132 KB |
Output is correct |
5 |
Correct |
73 ms |
19392 KB |
Output is correct |
6 |
Correct |
89 ms |
16316 KB |
Output is correct |
7 |
Correct |
85 ms |
15736 KB |
Output is correct |
8 |
Correct |
96 ms |
13708 KB |
Output is correct |
9 |
Correct |
112 ms |
15032 KB |
Output is correct |
10 |
Correct |
168 ms |
17088 KB |
Output is correct |
11 |
Correct |
121 ms |
15292 KB |
Output is correct |
12 |
Correct |
133 ms |
17792 KB |
Output is correct |
13 |
Correct |
104 ms |
12988 KB |
Output is correct |
14 |
Correct |
95 ms |
14260 KB |
Output is correct |
15 |
Correct |
163 ms |
16320 KB |
Output is correct |
16 |
Correct |
178 ms |
17668 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4440 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
0 ms |
4444 KB |
Output is correct |
4 |
Correct |
0 ms |
4444 KB |
Output is correct |
5 |
Correct |
0 ms |
4444 KB |
Output is correct |
6 |
Incorrect |
0 ms |
4444 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4440 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
0 ms |
4444 KB |
Output is correct |
4 |
Correct |
0 ms |
4444 KB |
Output is correct |
5 |
Correct |
0 ms |
4444 KB |
Output is correct |
6 |
Incorrect |
0 ms |
4444 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4440 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
0 ms |
4444 KB |
Output is correct |
4 |
Correct |
0 ms |
4444 KB |
Output is correct |
5 |
Correct |
0 ms |
4444 KB |
Output is correct |
6 |
Incorrect |
0 ms |
4444 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |