This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define fr first
#define sc second
#define pii pair<int, int>
#define pb push_back
#define szof(s) (int)s.size()
#define all(s) s.begin(), s.end()
#define fastInp ios_base::sync_with_stdio(0); cin.tie(0);
#define ll long long
#define mk make_pair
template<class T>void chmax(T &a, T b){if (a < b)a = b;}
template<class T>void chmin(T &a, T b){if (b < a)a = b;}
using namespace std;
const int MAX_N = (int)1e5 + 5;
const int MAX_M = (int)2e5 + 5;
const int MAX_Q = (int)1e5 + 5;
const int S = 300;
const int INF = 1e9;
vector <int> g[MAX_N];
vector <int> busy[MAX_Q];
int t[MAX_Q];
int n, m, q;
struct Subtask1_Solve { // O(M * N) time complexity
int dp[1005][1005];
int is_busy[1005], used_id = 0;
void run() {
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= n; j++) {
dp[i][j] = -INF;
if (i == j) {
dp[i][j] = 0;
}
}
}
for (int i = n; i >= 1; i--) {
for (int to : g[i]) {
for (int j = 1; j <= n; j++) {
if (dp[to][j] == INF) {
continue;
} else {
chmax(dp[i][j], 1 + dp[to][j]);
}
}
}
}
for (int i = 1; i <= q; i++) {
used_id++;
for (int el : busy[i]) {
is_busy[el] = used_id;
}
int mx = -1;
for (int j = 1; j <= n; j++) {
if (is_busy[j] != used_id) {
chmax(mx, dp[j][t[i]]);
}
}
cout << mx << endl;
}
}
};
struct Subtask2_Solve { // O(M) time complexity for 1 query
int dp[MAX_N];
void run() {
fill(dp, dp + MAX_N, -INF);
dp[t[1]] = 0;
int ans = -1;
for (int i = n; i >= 1; i--) {
for (int to : g[i]) {
if (dp[to] != -INF) {
chmax(dp[i], 1 + dp[to]);
}
}
if (binary_search(all(busy[1]), i) == false) {
chmax(ans, dp[i]);
}
}
cout << ans << endl;
}
};
struct Full_Solution {
vector <pii> far[MAX_N]; // vertex dist
// far[i][0] >= far[i][1] >= far[i][2] >= by distance
void precalc() {
for (int i = 1; i <= n; i++) {
far[i].pb({i, 0});
}
for (int i = 1; i <= n; i++) {
for (int to : g[i]) {
vector <pii> vec;
int l = 0, r = 0;
while (l < szof(far[i]) && r < szof(far[to]) && szof(vec) < S) {
if (far[i][l].sc + 1 > far[to][r].sc) {
vec.pb({far[i][l].fr, far[i][l].sc + 1});
l++;
} else {
vec.pb(far[to][r]);
r++;
}
}
if (szof(vec) < S) {
while (l < szof(far[i]) && szof(vec) < S) {
vec.pb({far[i][l].fr, far[i][l].sc + 1});
l++;
}
while (r < szof(far[to]) && szof(vec) < S) {
vec.pb(far[to][r]);
r++;
}
}
assert(szof(vec) <= S);
far[to] = vec;
}
}
}
void run() {
vector <int> is_busy(MAX_N, false);
vector <int> dp(MAX_N);
vector <int> busy_id(MAX_N, -1);
precalc();
for (int i = 1; i <= q; i++) {
for (int el : busy[i]) {
busy_id[el] = i;
}
if (szof(busy[i]) >= S) {
for (int j = 1; j <= n; j++) {
dp[j] = -INF;
}
dp[t[i]] = 0;
int ans = -1;
for (int v = n; v >= 1; v--) {
for (int to : g[v]) {
if (dp[to] != -INF) {
chmax(dp[v], 1 + dp[to]);
}
}
if (busy_id[v] != i) {
chmax(ans, dp[v]);
}
}
cout << ans << endl;
}
else { // szof(busy[i]) < S
int ans = -1;
for (auto [v, dist] : far[t[i]]) {
if (busy_id[v] != i) {
ans = dist;
break;
}
}
cout << ans << endl;
}
}
}
};
signed main() {
fastInp;
cin >> n >> m >> q;
for (int i = 1; i <= m; i++) {
int from, to;
cin >> from >> to;
g[from].pb(to);
}
for (int i = 1, sz; i <= q; i++) {
cin >> t[i] >> sz;
for (int j = 1; j <= sz; j++) {
int v;
cin >> v;
busy[i].pb(v);
}
}
Full_Solution T;
T.run();
}
/*
5 6 3
1 2
2 4
3 4
1 3
3 5
4 5
5 2 2 3
4 1 1
2 3 1 4 5
*/
Compilation message (stderr)
bitaro.cpp: In member function 'void Full_Solution::run()':
bitaro.cpp:151:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
151 | for (auto [v, dist] : far[t[i]]) {
| ^
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