Submission #892370

#	Time	Username	Problem	Language	Result	Execution time	Memory
892370		vjudge1	Sprinkler (JOI22_sprinkler)	C++17	3 / 100	697 ms	30636 KiB

sprinkler

#include <bits/stdc++.h>
 
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long
#define rnd(l, r) uniform_int_distribution<int>(l, r)(rng)
 
using namespace std;

void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);} 
int pow(int a,int b,int m){int ans=1;while(b){if(b&1){ans=(ans*a)%m;}b>>=1;a=(a*a)%m;}return ans;}
int binpow(int a,int b){int ans=1;while(b){if(b&1){ans=(ans*a);}b>>=1;a=(a*a);}return ans;}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int N = 2e5 + 10, inf = 1e9;

vector <int> g[N];
int cost[N];
 
int h[N][3];
int par[N];

void dfs(int v, int p){
	par[v] = p;
	for(auto to : g[v]){
		if(to == p)continue;
		dfs(to, v);
	}
}
main(){
	iostream::sync_with_stdio(false);	
    cin.tie(nullptr);
    cout.tie(nullptr);
	int n, l;
	cin >> n >> l;
	for(int i = 0; i < n - 1; i ++){
		int a, b;
		cin >> a >> b;
		g[a].pb(b);
		g[b].pb(a);
	}
	for(int i =1; i <= n; i++){
		cin >> cost[i];
		for(int j = 0; j <= 3; j++){
			h[i][j] = 1;
		}
	}
	
	int q;
	cin >> q;
	if(n <= 1000 && q <= 1000){
		while(q--){
			int tp;
			cin >> tp;
			if(tp == 1){
				int x, d, w;
				cin >> x >> d >> w;
				vector <int> dist(n + 1, inf);
				dist[x] = 0;
				queue <int> q;
				q.push(x);
				while(!q.empty()){
					int v = q.front();
					q.pop();
					for(auto to : g[v]){
						if(dist[to] > dist[v] + 1){
							dist[to] = dist[v] + 1;
							q.push(to);
						}
					}
				}
				
				for(int i = 1; i <= n; i++){
					if(dist[i] <= d){
						cost[i] = (cost[i] * w) % l;
					}
				}
			}else{
				int x;
				cin >> x;
				cout << cost[x] << endl;
			}
		}
	}else{
		dfs(1, 1);
		while(q--){
			int tp;
			cin >> tp;
			if(tp == 1){
				int x, d, w;
				cin >> x >> d >> w;
				for(int i = 0; i <= d; i++){
					h[x][i] = h[x][i] * w % l;
					x = par[x];
				}
			}else{
				int x;
				cin >> x;
				int res = cost[x];
				for(int i = 0; i <= 2; i++){
					res *= h[x][i];
					res %= l;
				}
				cout << res << endl;
			}
		}
	}
	
}
/*
 * Before implementing the problem:
	
	Do I understand the problem correctly?
	Which places are tricky? What do I need to remember to implement them correctly?
	Which place is the heaviest by implementation? Can I do it simpler?
	Which place is the slowest? Where do I need to be careful about constant factors and where I can choose slower but simpler implementation?
	----------------------------------
	If not AC:
 
	Did you remember to do everything to handle the tricky places you thought about before?
	Is the solution correct?
	Do I understand the problem correctly?
	----------------------------------
	If you have a test on which the solution gives wrong answer:
 
	Is the solution doing what it was supposed to do?
	Is the problem in the code or in the idea?
*/

Compilation message (stderr)

sprinkler.cpp:33:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   33 | main(){
      | ^~~~
sprinkler.cpp: In function 'void fp(std::string)':
sprinkler.cpp:13:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sprinkler.cpp:13:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
sprinkler.cpp: In function 'int main()':
sprinkler.cpp:48:12: warning: iteration 3 invokes undefined behavior [-Waggressive-loop-optimizations]
   48 |    h[i][j] = 1;
      |    ~~~~~~~~^~~
sprinkler.cpp:47:20: note: within this loop
   47 |   for(int j = 0; j <= 3; j++){
      |                  ~~^~~~
sprinkler.cpp:48:10: warning: array subscript 3 is above array bounds of 'long long int [3]' [-Warray-bounds]
   48 |    h[i][j] = 1;
      |    ~~~~~~^

• Subtask 1: 3 / 3
• Subtask 2: 0 / 9
• Subtask 3: 0 / 29
• Subtask 4: 0 / 12
• Subtask 5: 0 / 30
• Subtask 6: 0 / 17