#include <bits/stdc++.h>
using namespace std;
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
const int N = 2e5+4;
const int SQRT = 460;
int ans[N];
struct qr{
int l, r, i;
bool operator<(qr b){
return make_pair(l/SQRT, r) < make_pair(b.l/SQRT,b.r);
}
};
vector<qr> queries[SQRT];
int edges[N][2];
struct DSU {
vector<int> e;
DSU(int N) { e = vector<int>(N, -1); }
int get(int x) { return e[x] < 0 ? x : e[x] = get(e[x]); }
bool conn(int a, int b) { return get(a) == get(b); }
int size(int x) { return -e[get(x)]; }
void unite(int x, int y) {
x = get(x), y = get(y);
if (x == y) return;
if (e[x] > e[y]) swap(x, y);
e[x] += e[y];
e[y] = x;
}
};
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--; edges[i][0]=a; edges[i][1] = b;
}
for (int i=0; i<q; i++){
int l,r; cin>>l>>r; l--; r--;
qr p; p.l=l;p.r=r;p.i=i;
queries[l/SQRT].push_back(p);
}
for (int i=0; i<SQRT; i++) sort(queries[i].begin(), queries[i].end());
DSU dsu1(2*n);
DSU dsu2(2*n);
DSU dsu3(2*n);
int fM =0;
for (int t=0; t<SQRT; t++){
for (int i=0; i<2*n; i++) dsu2.e[i] = dsu1.e[i];
for (int i=0; i<2*n; i++) dsu3.e[i] = dsu1.e[i];
if (t*SQRT >= m) break;
int fm = 0;
int i = m-1; int j = queries[t].size()-1;
while (i>=0){
if (j<0) break;
qr p = queries[t][j];
while (p.r == i){
int f = 0;
for (int ll=t*SQRT; ll<p.l; ll++){
if (dsu3.conn(edges[ll][0],edges[ll][1])) f++;
dsu3.unite(edges[ll][0]+n, edges[ll][1]);
dsu3.unite(edges[ll][0], edges[ll][1]+n);
}
for (int ll=t*SQRT; ll<p.l; ll++){
int a = edges[ll][0]; int b = edges[ll][1];
int c = a+n; int d = b+n;
dsu3.e[a] = dsu2.e[a];
dsu3.e[b] = dsu2.e[b];
dsu3.e[c] = dsu2.e[c];
dsu3.e[d] = dsu2.e[d];
}
if (f || fm || fM) ans[p.i] = 1;
j--;
if (j<0) break;
p = queries[t][j];
}
if (j<0) break;
fm += dsu3.conn(edges[i][0], edges[i][1]);
dsu2.unite(edges[i][0] + n, edges[i][1]);
dsu2.unite(edges[i][0], edges[i][1] + n);
dsu3.unite(edges[i][0] + n, edges[i][1]);
dsu3.unite(edges[i][0], edges[i][1] + n);
i--;
}
for (int ll=SQRT*t; ll<min(m, SQRT*t + SQRT); ll++){
fM += dsu1.conn(edges[ll][0], edges[ll][1]);
dsu1.unite(edges[ll][0] + n, edges[ll][1]);
dsu1.unite(edges[ll][0], edges[ll][1] + n);
}
}
for (int i=0;i<q; i++) cout<<(ans[i]?"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 |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Correct |
0 ms |
2396 KB |
Output is correct |
4 |
Correct |
0 ms |
2396 KB |
Output is correct |
5 |
Correct |
0 ms |
2396 KB |
Output is correct |
6 |
Correct |
0 ms |
2396 KB |
Output is correct |
7 |
Runtime error |
128 ms |
262144 KB |
Execution killed with signal 9 |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Correct |
0 ms |
2396 KB |
Output is correct |
4 |
Correct |
0 ms |
2396 KB |
Output is correct |
5 |
Correct |
0 ms |
2396 KB |
Output is correct |
6 |
Correct |
0 ms |
2396 KB |
Output is correct |
7 |
Runtime error |
128 ms |
262144 KB |
Execution killed with signal 9 |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Correct |
134 ms |
8384 KB |
Output is correct |
4 |
Correct |
221 ms |
10408 KB |
Output is correct |
5 |
Correct |
197 ms |
10176 KB |
Output is correct |
6 |
Correct |
134 ms |
8120 KB |
Output is correct |
7 |
Correct |
141 ms |
7976 KB |
Output is correct |
8 |
Correct |
104 ms |
7332 KB |
Output is correct |
9 |
Correct |
161 ms |
8124 KB |
Output is correct |
10 |
Correct |
217 ms |
10680 KB |
Output is correct |
11 |
Correct |
135 ms |
8120 KB |
Output is correct |
12 |
Correct |
204 ms |
9784 KB |
Output is correct |
13 |
Correct |
67 ms |
6856 KB |
Output is correct |
14 |
Correct |
107 ms |
7084 KB |
Output is correct |
15 |
Correct |
176 ms |
9400 KB |
Output is correct |
16 |
Correct |
219 ms |
10944 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Correct |
0 ms |
2396 KB |
Output is correct |
4 |
Correct |
0 ms |
2396 KB |
Output is correct |
5 |
Correct |
0 ms |
2396 KB |
Output is correct |
6 |
Correct |
0 ms |
2396 KB |
Output is correct |
7 |
Runtime error |
128 ms |
262144 KB |
Execution killed with signal 9 |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Correct |
0 ms |
2396 KB |
Output is correct |
4 |
Correct |
0 ms |
2396 KB |
Output is correct |
5 |
Correct |
0 ms |
2396 KB |
Output is correct |
6 |
Correct |
0 ms |
2396 KB |
Output is correct |
7 |
Runtime error |
128 ms |
262144 KB |
Execution killed with signal 9 |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
0 ms |
2396 KB |
Output is correct |
3 |
Correct |
0 ms |
2396 KB |
Output is correct |
4 |
Correct |
0 ms |
2396 KB |
Output is correct |
5 |
Correct |
0 ms |
2396 KB |
Output is correct |
6 |
Correct |
0 ms |
2396 KB |
Output is correct |
7 |
Runtime error |
128 ms |
262144 KB |
Execution killed with signal 9 |
8 |
Halted |
0 ms |
0 KB |
- |