/**
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 = 320;
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 |
11 ms |
8184 KB |
Output is correct |
2 |
Correct |
11 ms |
8364 KB |
Output is correct |
3 |
Correct |
9 ms |
8364 KB |
Output is correct |
4 |
Correct |
10 ms |
8364 KB |
Output is correct |
5 |
Correct |
15 ms |
8920 KB |
Output is correct |
6 |
Correct |
13 ms |
8920 KB |
Output is correct |
7 |
Correct |
13 ms |
8920 KB |
Output is correct |
8 |
Correct |
22 ms |
11836 KB |
Output is correct |
9 |
Correct |
22 ms |
11968 KB |
Output is correct |
10 |
Correct |
20 ms |
11968 KB |
Output is correct |
11 |
Correct |
23 ms |
11968 KB |
Output is correct |
12 |
Correct |
17 ms |
11968 KB |
Output is correct |
13 |
Correct |
25 ms |
11968 KB |
Output is correct |
14 |
Correct |
21 ms |
11968 KB |
Output is correct |
15 |
Correct |
17 ms |
11968 KB |
Output is correct |
16 |
Correct |
21 ms |
11968 KB |
Output is correct |
17 |
Correct |
20 ms |
11968 KB |
Output is correct |
18 |
Correct |
18 ms |
11968 KB |
Output is correct |
19 |
Correct |
19 ms |
11968 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
8184 KB |
Output is correct |
2 |
Correct |
11 ms |
8364 KB |
Output is correct |
3 |
Correct |
9 ms |
8364 KB |
Output is correct |
4 |
Correct |
10 ms |
8364 KB |
Output is correct |
5 |
Correct |
15 ms |
8920 KB |
Output is correct |
6 |
Correct |
13 ms |
8920 KB |
Output is correct |
7 |
Correct |
13 ms |
8920 KB |
Output is correct |
8 |
Correct |
22 ms |
11836 KB |
Output is correct |
9 |
Correct |
22 ms |
11968 KB |
Output is correct |
10 |
Correct |
20 ms |
11968 KB |
Output is correct |
11 |
Correct |
23 ms |
11968 KB |
Output is correct |
12 |
Correct |
17 ms |
11968 KB |
Output is correct |
13 |
Correct |
25 ms |
11968 KB |
Output is correct |
14 |
Correct |
21 ms |
11968 KB |
Output is correct |
15 |
Correct |
17 ms |
11968 KB |
Output is correct |
16 |
Correct |
21 ms |
11968 KB |
Output is correct |
17 |
Correct |
20 ms |
11968 KB |
Output is correct |
18 |
Correct |
18 ms |
11968 KB |
Output is correct |
19 |
Correct |
19 ms |
11968 KB |
Output is correct |
20 |
Correct |
843 ms |
16360 KB |
Output is correct |
21 |
Correct |
751 ms |
16360 KB |
Output is correct |
22 |
Correct |
850 ms |
16388 KB |
Output is correct |
23 |
Correct |
888 ms |
16388 KB |
Output is correct |
24 |
Correct |
1491 ms |
260860 KB |
Output is correct |
25 |
Correct |
1423 ms |
272232 KB |
Output is correct |
26 |
Correct |
1383 ms |
272232 KB |
Output is correct |
27 |
Correct |
1455 ms |
419152 KB |
Output is correct |
28 |
Correct |
1492 ms |
419280 KB |
Output is correct |
29 |
Correct |
1567 ms |
419452 KB |
Output is correct |
30 |
Correct |
1592 ms |
419452 KB |
Output is correct |
31 |
Correct |
1584 ms |
419452 KB |
Output is correct |
32 |
Correct |
1423 ms |
419452 KB |
Output is correct |
33 |
Correct |
1114 ms |
419452 KB |
Output is correct |
34 |
Correct |
1028 ms |
419452 KB |
Output is correct |
35 |
Correct |
1090 ms |
419452 KB |
Output is correct |
36 |
Correct |
1316 ms |
419452 KB |
Output is correct |
37 |
Correct |
1323 ms |
419452 KB |
Output is correct |
38 |
Correct |
1352 ms |
419452 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
8184 KB |
Output is correct |
2 |
Correct |
11 ms |
8364 KB |
Output is correct |
3 |
Correct |
9 ms |
8364 KB |
Output is correct |
4 |
Correct |
10 ms |
8364 KB |
Output is correct |
5 |
Correct |
15 ms |
8920 KB |
Output is correct |
6 |
Correct |
13 ms |
8920 KB |
Output is correct |
7 |
Correct |
13 ms |
8920 KB |
Output is correct |
8 |
Correct |
22 ms |
11836 KB |
Output is correct |
9 |
Correct |
22 ms |
11968 KB |
Output is correct |
10 |
Correct |
20 ms |
11968 KB |
Output is correct |
11 |
Correct |
23 ms |
11968 KB |
Output is correct |
12 |
Correct |
17 ms |
11968 KB |
Output is correct |
13 |
Correct |
25 ms |
11968 KB |
Output is correct |
14 |
Correct |
21 ms |
11968 KB |
Output is correct |
15 |
Correct |
17 ms |
11968 KB |
Output is correct |
16 |
Correct |
21 ms |
11968 KB |
Output is correct |
17 |
Correct |
20 ms |
11968 KB |
Output is correct |
18 |
Correct |
18 ms |
11968 KB |
Output is correct |
19 |
Correct |
19 ms |
11968 KB |
Output is correct |
20 |
Correct |
843 ms |
16360 KB |
Output is correct |
21 |
Correct |
751 ms |
16360 KB |
Output is correct |
22 |
Correct |
850 ms |
16388 KB |
Output is correct |
23 |
Correct |
888 ms |
16388 KB |
Output is correct |
24 |
Correct |
1491 ms |
260860 KB |
Output is correct |
25 |
Correct |
1423 ms |
272232 KB |
Output is correct |
26 |
Correct |
1383 ms |
272232 KB |
Output is correct |
27 |
Correct |
1455 ms |
419152 KB |
Output is correct |
28 |
Correct |
1492 ms |
419280 KB |
Output is correct |
29 |
Correct |
1567 ms |
419452 KB |
Output is correct |
30 |
Correct |
1592 ms |
419452 KB |
Output is correct |
31 |
Correct |
1584 ms |
419452 KB |
Output is correct |
32 |
Correct |
1423 ms |
419452 KB |
Output is correct |
33 |
Correct |
1114 ms |
419452 KB |
Output is correct |
34 |
Correct |
1028 ms |
419452 KB |
Output is correct |
35 |
Correct |
1090 ms |
419452 KB |
Output is correct |
36 |
Correct |
1316 ms |
419452 KB |
Output is correct |
37 |
Correct |
1323 ms |
419452 KB |
Output is correct |
38 |
Correct |
1352 ms |
419452 KB |
Output is correct |
39 |
Correct |
1751 ms |
419452 KB |
Output is correct |
40 |
Correct |
1608 ms |
419452 KB |
Output is correct |
41 |
Correct |
1520 ms |
419452 KB |
Output is correct |
42 |
Correct |
1954 ms |
419452 KB |
Output is correct |
43 |
Correct |
1493 ms |
419452 KB |
Output is correct |
44 |
Correct |
922 ms |
419452 KB |
Output is correct |
45 |
Correct |
899 ms |
419452 KB |
Output is correct |
46 |
Correct |
875 ms |
419452 KB |
Output is correct |
47 |
Correct |
962 ms |
419452 KB |
Output is correct |
48 |
Correct |
888 ms |
419452 KB |
Output is correct |
49 |
Correct |
1937 ms |
419488 KB |
Output is correct |
50 |
Correct |
1837 ms |
419488 KB |
Output is correct |
51 |
Correct |
814 ms |
419488 KB |
Output is correct |
52 |
Correct |
816 ms |
419488 KB |
Output is correct |
53 |
Correct |
1736 ms |
419488 KB |
Output is correct |
54 |
Correct |
1506 ms |
419488 KB |
Output is correct |
55 |
Correct |
1641 ms |
419488 KB |
Output is correct |
56 |
Correct |
1693 ms |
419488 KB |
Output is correct |
57 |
Correct |
901 ms |
419488 KB |
Output is correct |
58 |
Correct |
907 ms |
419488 KB |
Output is correct |
59 |
Correct |
843 ms |
419488 KB |
Output is correct |
60 |
Correct |
839 ms |
419488 KB |
Output is correct |
61 |
Correct |
1683 ms |
419488 KB |
Output is correct |
62 |
Correct |
1688 ms |
419488 KB |
Output is correct |
63 |
Correct |
1677 ms |
419488 KB |
Output is correct |
64 |
Execution timed out |
2066 ms |
419540 KB |
Time limit exceeded |
65 |
Halted |
0 ms |
0 KB |
- |