#include <bits/stdc++.h>
const int32_t MAX_N = 1e5;
const int32_t BUCKET_SIZE = 300;
const int32_t INF = 2e9;
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 + 1) {
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].first + 1, v2[ind2].second });
}
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].first + 1, v2[ind2].second });
}
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;
};
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]);
}
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) {
nodes[i].dp = Merge(nodes[i].dp, x->dp);
}
}
}
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);
for(int32_t i = 1; i <= t; i++) {
if(isForbidden[i]) {
dp[i] = -INF;
}
else {
dp[i] = 0;
}
for(auto &x : nodes[i].v) {
dp[i] = std::max(dp[i], dp[x->id] + 1);
}
}
return std::max(dp[t], -1);
}
};
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
joi2019_ho_t1.cpp: In function 'std::vector<std::pair<int, int> > Merge(const std::vector<std::pair<int, int> >&, const std::vector<std::pair<int, int> >&)':
joi2019_ho_t1.cpp:16:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while((ind1 < v1.size() || ind2 < v2.size()) && ans.size() < BUCKET_SIZE) {
~~~~~^~~~~~~~~~~
joi2019_ho_t1.cpp:16:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while((ind1 < v1.size() || ind2 < v2.size()) && ans.size() < BUCKET_SIZE) {
~~~~~^~~~~~~~~~~
joi2019_ho_t1.cpp:17:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if(ind1 < v1.size()) {
~~~~~^~~~~~~~~~~
joi2019_ho_t1.cpp:18:12: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
if(ind2 < v2.size()) {
~~~~~^~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
4 ms |
5760 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
4 ms |
5760 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
4 ms |
5760 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
