/**
Solution:
Idea: We can precompute for each node the sqrt(n) furthest nodes with a simple dp. Then for each query
if the number of forbidden nodes is less than sqrt(n) then for sure the answer will be among the precomputed
otherwise we can simply solve it with a brutefore since the queries of this type will be less than sqrt(n).
*/
#include <bits/stdc++.h>
const int32_t MAX_N = 1e5;
const int32_t BUCKET_SIZE = 200;
bool isInVector[MAX_N + 5];
bool isForbidden[MAX_N + 5];
std::vector< std::pair< int32_t, int32_t > > Merge(const std::vector< std::pair< int32_t, int32_t> > &v1,
const std::vector< std::pair< int32_t, int32_t > > &v2) {
std::vector< std::pair< int32_t, int32_t > > ans;
int32_t ind1 = 0, ind2 = 0;
while((ind1 < v1.size() || ind2 < v2.size()) && ans.size() < BUCKET_SIZE) {
if(ind1 < v1.size()) {
if(ind2 < v2.size()) {
if(v1[ind1].first >= v2[ind2].first) {
if(!isInVector[v1[ind1].second]) {
isInVector[v1[ind1].second] = true;
ans.push_back(v1[ind1]);
}
ind1++;
}
else {
if(!isInVector[v2[ind2].second]) {
isInVector[v2[ind2].second] = true;
ans.push_back(v2[ind2]);
}
ind2++;
}
}
else {
if(!isInVector[v1[ind1].second]) {
isInVector[v1[ind1].second] = true;
ans.push_back(v1[ind1]);
}
ind1++;
}
}
else {
if(!isInVector[v2[ind2].second]) {
isInVector[v2[ind2].second] = true;
ans.push_back(v2[ind2]);
}
ind2++;
}
}
for(auto &x : ans) {
isInVector[x.second] = false;
}
return ans;
}
class Graph {
private:
struct Node {
int32_t id;
std::vector< std::pair< int32_t, int32_t > > dp;
std::vector< Node* > v, rev;
};
int32_t cntNodes;
Node nodes[MAX_N + 5];
public:
void Init(int32_t _cntNodes) {
cntNodes = _cntNodes;
for(int32_t i = 1; i <= cntNodes; i++) {
nodes[i].id = i;
}
}
void AddEdge(int32_t from, int32_t to) {
nodes[from].v.push_back(&nodes[to]);
nodes[to].rev.push_back(&nodes[from]);
}
void Precompute() {
for(int32_t i = 1; i <= cntNodes; i++) {
std::vector< std::pair< int32_t, int32_t > > dists;
nodes[i].dp.push_back({ 0, i });
for(auto &x : nodes[i].v) {
auto aux = x->dp;
for(auto &y : aux) {
y.first++;
}
nodes[i].dp = Merge(nodes[i].dp, aux);
}
}
}
int32_t SolveSmallK(int32_t t) {
for(auto &x : nodes[t].dp) {
if(!isForbidden[x.second]) {
return x.first;
}
}
return -1;
}
int32_t SolveBigK(int32_t t) {
std::vector< int32_t > dp(t + 1, 0);
int32_t ans = (isForbidden[t] ? -1 : 0);
for(int32_t i = t - 1; i >= 1; i--) {
bool isChanged = false;
for(auto &x : nodes[i].rev) {
if(x->id <= t && (x->id == t || dp[x->id] != 0)) {
dp[i] = std::max(dp[i], dp[x->id] + 1);
isChanged = true;
}
}
if(isChanged && !isForbidden[i]) {
ans = std::max(ans, dp[i]);
}
}
return ans;
}
};
Graph g;
int main() {
std::ios_base::sync_with_stdio(false);
std::cin.tie(nullptr);
int32_t n, m, q;
std::cin >> n >> m >> q;
g.Init(n);
for(int32_t i = 0; i < m; i++) {
int32_t u, v;
std::cin >> u >> v;
g.AddEdge(v, u);
}
g.Precompute();
for(int32_t i = 0; i < q; i++) {
int32_t t, k;
std::cin >> t >> k;
std::vector< int32_t > c(k);
for(int32_t j = 0; j < k; j++) {
std::cin >> c[j];
isForbidden[c[j]] = true;
}
if(k >= BUCKET_SIZE) {
std::cout << g.SolveBigK(t) << '\n';
}
else {
std::cout << g.SolveSmallK(t) << '\n';
}
for(int32_t j = 0; j < k; j++) {
isForbidden[c[j]] = false;
}
}
}
Compilation message
bitaro.cpp: In function 'std::vector<std::pair<int, int> > Merge(const std::vector<std::pair<int, int> >&, const std::vector<std::pair<int, int> >&)':
bitaro.cpp:20:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while((ind1 < v1.size() || ind2 < v2.size()) && ans.size() < BUCKET_SIZE) {
~~~~~^~~~~~~~~~~
bitaro.cpp:20:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while((ind1 < v1.size() || ind2 < v2.size()) && ans.size() < BUCKET_SIZE) {
~~~~~^~~~~~~~~~~
bitaro.cpp:21:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if(ind1 < v1.size()) {
~~~~~^~~~~~~~~~~
bitaro.cpp:22:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if(ind2 < v2.size()) {
~~~~~^~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
8184 KB |
Output is correct |
2 |
Correct |
9 ms |
8188 KB |
Output is correct |
3 |
Correct |
9 ms |
8264 KB |
Output is correct |
4 |
Correct |
9 ms |
8280 KB |
Output is correct |
5 |
Correct |
14 ms |
8792 KB |
Output is correct |
6 |
Correct |
17 ms |
8808 KB |
Output is correct |
7 |
Correct |
13 ms |
8980 KB |
Output is correct |
8 |
Correct |
20 ms |
10400 KB |
Output is correct |
9 |
Correct |
20 ms |
10400 KB |
Output is correct |
10 |
Correct |
18 ms |
10400 KB |
Output is correct |
11 |
Correct |
18 ms |
10400 KB |
Output is correct |
12 |
Correct |
15 ms |
10400 KB |
Output is correct |
13 |
Correct |
18 ms |
10400 KB |
Output is correct |
14 |
Correct |
16 ms |
10400 KB |
Output is correct |
15 |
Correct |
18 ms |
10400 KB |
Output is correct |
16 |
Correct |
17 ms |
10400 KB |
Output is correct |
17 |
Correct |
19 ms |
10400 KB |
Output is correct |
18 |
Correct |
9 ms |
10400 KB |
Output is correct |
19 |
Correct |
17 ms |
10400 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
8184 KB |
Output is correct |
2 |
Correct |
9 ms |
8188 KB |
Output is correct |
3 |
Correct |
9 ms |
8264 KB |
Output is correct |
4 |
Correct |
9 ms |
8280 KB |
Output is correct |
5 |
Correct |
14 ms |
8792 KB |
Output is correct |
6 |
Correct |
17 ms |
8808 KB |
Output is correct |
7 |
Correct |
13 ms |
8980 KB |
Output is correct |
8 |
Correct |
20 ms |
10400 KB |
Output is correct |
9 |
Correct |
20 ms |
10400 KB |
Output is correct |
10 |
Correct |
18 ms |
10400 KB |
Output is correct |
11 |
Correct |
18 ms |
10400 KB |
Output is correct |
12 |
Correct |
15 ms |
10400 KB |
Output is correct |
13 |
Correct |
18 ms |
10400 KB |
Output is correct |
14 |
Correct |
16 ms |
10400 KB |
Output is correct |
15 |
Correct |
18 ms |
10400 KB |
Output is correct |
16 |
Correct |
17 ms |
10400 KB |
Output is correct |
17 |
Correct |
19 ms |
10400 KB |
Output is correct |
18 |
Correct |
9 ms |
10400 KB |
Output is correct |
19 |
Correct |
17 ms |
10400 KB |
Output is correct |
20 |
Correct |
568 ms |
14720 KB |
Output is correct |
21 |
Correct |
546 ms |
14972 KB |
Output is correct |
22 |
Correct |
603 ms |
14972 KB |
Output is correct |
23 |
Correct |
580 ms |
14972 KB |
Output is correct |
24 |
Correct |
1041 ms |
157856 KB |
Output is correct |
25 |
Correct |
1054 ms |
162272 KB |
Output is correct |
26 |
Correct |
1008 ms |
162520 KB |
Output is correct |
27 |
Correct |
1027 ms |
219364 KB |
Output is correct |
28 |
Correct |
1174 ms |
219440 KB |
Output is correct |
29 |
Correct |
1108 ms |
219472 KB |
Output is correct |
30 |
Correct |
1147 ms |
219472 KB |
Output is correct |
31 |
Correct |
1182 ms |
219472 KB |
Output is correct |
32 |
Correct |
1130 ms |
219472 KB |
Output is correct |
33 |
Correct |
904 ms |
219472 KB |
Output is correct |
34 |
Correct |
867 ms |
219472 KB |
Output is correct |
35 |
Correct |
872 ms |
219472 KB |
Output is correct |
36 |
Correct |
1042 ms |
219472 KB |
Output is correct |
37 |
Correct |
1067 ms |
219472 KB |
Output is correct |
38 |
Correct |
1051 ms |
219472 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
8184 KB |
Output is correct |
2 |
Correct |
9 ms |
8188 KB |
Output is correct |
3 |
Correct |
9 ms |
8264 KB |
Output is correct |
4 |
Correct |
9 ms |
8280 KB |
Output is correct |
5 |
Correct |
14 ms |
8792 KB |
Output is correct |
6 |
Correct |
17 ms |
8808 KB |
Output is correct |
7 |
Correct |
13 ms |
8980 KB |
Output is correct |
8 |
Correct |
20 ms |
10400 KB |
Output is correct |
9 |
Correct |
20 ms |
10400 KB |
Output is correct |
10 |
Correct |
18 ms |
10400 KB |
Output is correct |
11 |
Correct |
18 ms |
10400 KB |
Output is correct |
12 |
Correct |
15 ms |
10400 KB |
Output is correct |
13 |
Correct |
18 ms |
10400 KB |
Output is correct |
14 |
Correct |
16 ms |
10400 KB |
Output is correct |
15 |
Correct |
18 ms |
10400 KB |
Output is correct |
16 |
Correct |
17 ms |
10400 KB |
Output is correct |
17 |
Correct |
19 ms |
10400 KB |
Output is correct |
18 |
Correct |
9 ms |
10400 KB |
Output is correct |
19 |
Correct |
17 ms |
10400 KB |
Output is correct |
20 |
Correct |
568 ms |
14720 KB |
Output is correct |
21 |
Correct |
546 ms |
14972 KB |
Output is correct |
22 |
Correct |
603 ms |
14972 KB |
Output is correct |
23 |
Correct |
580 ms |
14972 KB |
Output is correct |
24 |
Correct |
1041 ms |
157856 KB |
Output is correct |
25 |
Correct |
1054 ms |
162272 KB |
Output is correct |
26 |
Correct |
1008 ms |
162520 KB |
Output is correct |
27 |
Correct |
1027 ms |
219364 KB |
Output is correct |
28 |
Correct |
1174 ms |
219440 KB |
Output is correct |
29 |
Correct |
1108 ms |
219472 KB |
Output is correct |
30 |
Correct |
1147 ms |
219472 KB |
Output is correct |
31 |
Correct |
1182 ms |
219472 KB |
Output is correct |
32 |
Correct |
1130 ms |
219472 KB |
Output is correct |
33 |
Correct |
904 ms |
219472 KB |
Output is correct |
34 |
Correct |
867 ms |
219472 KB |
Output is correct |
35 |
Correct |
872 ms |
219472 KB |
Output is correct |
36 |
Correct |
1042 ms |
219472 KB |
Output is correct |
37 |
Correct |
1067 ms |
219472 KB |
Output is correct |
38 |
Correct |
1051 ms |
219472 KB |
Output is correct |
39 |
Correct |
1247 ms |
219472 KB |
Output is correct |
40 |
Correct |
1187 ms |
219472 KB |
Output is correct |
41 |
Correct |
1127 ms |
219472 KB |
Output is correct |
42 |
Correct |
1542 ms |
219472 KB |
Output is correct |
43 |
Correct |
1081 ms |
219472 KB |
Output is correct |
44 |
Correct |
620 ms |
219472 KB |
Output is correct |
45 |
Correct |
604 ms |
219472 KB |
Output is correct |
46 |
Correct |
620 ms |
219472 KB |
Output is correct |
47 |
Correct |
686 ms |
219472 KB |
Output is correct |
48 |
Correct |
614 ms |
219472 KB |
Output is correct |
49 |
Correct |
1293 ms |
219508 KB |
Output is correct |
50 |
Correct |
1236 ms |
219508 KB |
Output is correct |
51 |
Correct |
606 ms |
219508 KB |
Output is correct |
52 |
Correct |
611 ms |
219508 KB |
Output is correct |
53 |
Correct |
1290 ms |
219508 KB |
Output is correct |
54 |
Correct |
1280 ms |
219508 KB |
Output is correct |
55 |
Correct |
1184 ms |
219508 KB |
Output is correct |
56 |
Correct |
1216 ms |
219508 KB |
Output is correct |
57 |
Correct |
632 ms |
219508 KB |
Output is correct |
58 |
Correct |
635 ms |
219508 KB |
Output is correct |
59 |
Correct |
580 ms |
219508 KB |
Output is correct |
60 |
Correct |
590 ms |
219508 KB |
Output is correct |
61 |
Correct |
1642 ms |
219508 KB |
Output is correct |
62 |
Correct |
1452 ms |
219508 KB |
Output is correct |
63 |
Correct |
1339 ms |
219508 KB |
Output is correct |
64 |
Execution timed out |
2070 ms |
219564 KB |
Time limit exceeded |
65 |
Halted |
0 ms |
0 KB |
- |