Submission #635041

#	Time	Username	Problem	Language	Result	Execution time	Memory
635041		IWTIM	Bridges (APIO19_bridges)	C++14	100 / 100	2290 ms	233728 KiB

bridges

# include <bits/stdc++.h>
using namespace std;
using ll = long long;
using db = long double; // or double, if TL is tight
using str = string; // yay python! 
 
// pairs
using pii = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;
#define mp make_pair
#define f first
#define s second
 
#define tcT template<class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>; 
tcT, size_t SZ> using AR = array<T,SZ>; 
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<db>;
using vs = V<str>;
using vpi = V<pii>;
using vpl = V<pl>;
using vpd = V<pd>;
 
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend() 
#define sor(x) sort(all(x)) 
#define rsz resize
#define ins insert 
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
 
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define rep(a) F0R(_,a)
#define each(a,x) for (auto& a: x)
const int MOD = 998244353;
const int MX = 2e5+5;
const ll BIG = 1e18; // not too close to LLONG_MAX
const db PI = acos((db)-1);
const int dx[4]{1,0,-1,0}, dy[4]{0,1,0,-1}; // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 
template<class T> using pqg = priority_queue<T,vector<T>,greater<T>>;
struct DSU {
	vi e; void init(int N) { e = vi(N,-1); }
	int get(int x) { return e[x] < 0 ? x : e[x] = get(e[x]); } 
	bool sameSet(int a, int b) { return get(a) == get(b); }
	int size(int x) { return -e[get(x)]; }
	bool unite(int x, int y) { // union by size
		x = get(x), y = get(y); if (x == y) return 0;
		if (e[x] > e[y]) swap(x,y);
		e[x] += e[y]; e[y] = x; return 1;
	}
};
/*
inline namespace Helpers {
	//////////// is_iterable
	// https://stackoverflow.com/questions/13830158/check-if-a-variable-type-is-iterable
	// this gets used only when we can call begin() and end() on that type
	tcT, class = void> struct is_iterable : false_type {};
	tcT> struct is_iterable<T, void_t<decltype(begin(declval<T>())),
	                                  decltype(end(declval<T>()))
	                                 >
	                       > : true_type {};
	tcT> constexpr bool is_iterable_v = is_iterable<T>::value;
 
	//////////// is_readable
	tcT, class = void> struct is_readable : false_type {};
	tcT> struct is_readable<T,
	        typename std::enable_if_t<
	            is_same_v<decltype(cin >> declval<T&>()), istream&>
	        >
	    > : true_type {};
	tcT> constexpr bool is_readable_v = is_readable<T>::value;
 
	//////////// is_printable
	// // https://nafe.es/posts/2020-02-29-is-printable/
	tcT, class = void> struct is_printable : false_type {};
	tcT> struct is_printable<T,
	        typename std::enable_if_t<
	            is_same_v<decltype(cout << declval<T>()), ostream&>
	        >
	    > : true_type {};
	tcT> constexpr bool is_printable_v = is_printable<T>::value;
}*/
using ll = long long;
using db = long double; // or double, if TL is tight
using str = string; // yay python! 
 
// pairs
using pii = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;
#define mp make_pair
#define f first
#define s second
 
#define tcT template<class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>; 
tcT, size_t SZ> using AR = array<T,SZ>; 
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<db>;
using vs = V<str>;
using vpi = V<pii>;
using vpl = V<pl>;
using vpd = V<pd>;
 
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend() 
#define sor(x) sort(all(x)) 
#define rsz resize
#define ins insert 
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
 
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define rep(a) F0R(_,a)
#define each(a,x) for (auto& a: x)
template<class T> using pqg = priority_queue<T,vector<T>,greater<T>>;
 
/*
inline namespace Helpers {
	//////////// is_iterable
	// https://stackoverflow.com/questions/13830158/check-if-a-variable-type-is-iterable
	// this gets used only when we can call begin() and end() on that type
	tcT, class = void> struct is_iterable : false_type {};
	tcT> struct is_iterable<T, void_t<decltype(begin(declval<T>())),
	                                  decltype(end(declval<T>()))
	                                 >
	                       > : true_type {};
	tcT> constexpr bool is_iterable_v = is_iterable<T>::value;
 
	//////////// is_readable
	tcT, class = void> struct is_readable : false_type {};
	tcT> struct is_readable<T,
	        typename std::enable_if_t<
	            is_same_v<decltype(cin >> declval<T&>()), istream&>
	        >
	    > : true_type {};
	tcT> constexpr bool is_readable_v = is_readable<T>::value;
 
	//////////// is_printable
	// // https://nafe.es/posts/2020-02-29-is-printable/
	tcT, class = void> struct is_printable : false_type {};
	tcT> struct is_printable<T,
	        typename std::enable_if_t<
	            is_same_v<decltype(cout << declval<T>()), ostream&>
	        >
	    > : true_type {};
	tcT> constexpr bool is_printable_v = is_printable<T>::value;
}*/
const int N = 3e5 + 5, B = 700;
int sz[N],n,m,a[N],b[N],c[N],x[N],y[N],ty[N],q;
int p[N], cur[N], fix[N],ans[N];
vector <int> toadd[N];
vector < pii > upd, que,con;
stack < pair <pii, pii > > st;
int get_col(int a) {
	if (a == p[a]) return a;
	else return get_col(p[a]);
}
void col(int a, int b) {
    //cout<<"col  "<<a<<" "<<b<<"\n";
	a = get_col(a);
	b = get_col(b);
	
	if (sz[a] < sz[b]) swap(a,b);
	if (a == b) return ;
	st.push({{a,b},{sz[a],sz[b]}});
	sz[a] += sz[b];
	sz[b] = 0;
	p[b] = a;
}
void rollback(int szz) {
	while (st.size() > szz) {
		auto x = st.top();
		st.pop();
		int a = x.f.f, b = x.f.s, sza = x.s.f, szb = x.s.s; 
		sz[a] = sza; sz[b] = szb; p[a] = a; p[b] = b;
	}
}
void init() {
	for (int i = 1; i <= max(n,m); i++) {
		fix[i] = 0; sz[i] = 1; p[i] = i;
	}
	con.clear(); upd.clear(); que.clear();
}
main() {
	std::ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0);
	cin>>n>>m;
	for (int i = 1; i <= m; i++) {
		cin>>a[i]>>b[i]>>c[i];
	}
	cin>>q;
	for (int i = 1; i <= q; i++) {
		cin>>ty[i]>>x[i]>>y[i];
	}
	init();
	for (int le = 1; le <= q; le += B) {
		int ri = min(le + B - 1, q);
		for (int i = le; i <= ri; i++) {
			if (ty[i] == 1) {
				upd.pb({y[i], x[i]});
				fix[x[i]] = 1;
			} else {
				que.pb({y[i], i});
			}
		} 
		for (int i = 1; i <= m; i++) {
			if (!fix[i]) con.pb({c[i], i});
			cur[i] = c[i];
		}
		for (int i = le; i <= ri; i++) {
		    if (ty[i] == 1) c[x[i]] = y[i];
		}
		for (int i = le; i <= ri; i++) {
			if (ty[i] == 1) {
				cur[x[i]] = y[i];
			} else {
				for (auto id : upd) {
					if (cur[id.s] >= y[i]) toadd[i].pb(id.s);// add and rollback
				}
			}
		}
		sort(que.rbegin(),que.rend());
		sort(con.rbegin(),con.rend());
		int curid = 0;
		for (int i = 0; i < que.size(); i++) {
			while (curid < con.size() && con[curid].f >= que[i].f) {
				col(a[con[curid].s], b[con[curid].s]);
				curid++;
			}
			int szz = st.size();
			for (int id : toadd[que[i].s]) {
				col(a[id],b[id]);
			}
			ans[que[i].s] = sz[get_col(x[que[i].s])];
			rollback(szz);
		}
		init();
	}
	for (int i = 1; i <= q; i++) {
		if (ty[i] == 2) cout<<ans[i]<<"\n";
	}
}

Compilation message (stderr)

bridges.cpp: In function 'void rollback(int)':
bridges.cpp:204:19: warning: comparison of integer expressions of different signedness: 'std::stack<std::pair<std::pair<int, int>, std::pair<int, int> > >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  204 |  while (st.size() > szz) {
      |         ~~~~~~~~~~^~~~~
bridges.cpp: At global scope:
bridges.cpp:217:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  217 | main() {
      | ^~~~
bridges.cpp: In function 'int main()':
bridges.cpp:257:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int>, std::allocator<std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  257 |   for (int i = 0; i < que.size(); i++) {
      |                   ~~^~~~~~~~~~~~
bridges.cpp:258:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int>, std::allocator<std::pair<int, int> > >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  258 |    while (curid < con.size() && con[curid].f >= que[i].f) {
      |           ~~~~~~^~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 16 / 16
• Subtask 3: 17 / 17
• Subtask 4: 14 / 14
• Subtask 5: 13 / 13
• Subtask 6: 27 / 27