Submission #314448

#	Time	Username	Problem	Language	Result	Execution time	Memory
314448		limabeans	Trampoline (info1cup20_trampoline)	C++17	100 / 100	878 ms	55016 KiB

trampoline

#include <bits/stdc++.h>
using namespace std;

template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl





using ll = long long;


const int maxn = 2e5 + 5;
const int LOG = 21;

int n,m,t;
map<pair<int,int>,int> mp;
int X[maxn], Y[maxn];

vector<int> xord;
vector<int> row[maxn];

int par[LOG+1][maxn];


bool solve(int x1, int y1, int x2, int y2) {
    if (x1>x2) return false;
    if (y1>y2) return false;
    if (x1==x2) return true;

    int xi = std::lower_bound(xord.begin(),xord.end(),x1)-xord.begin();
    if (xi==(int)xord.size() || xord[xi]!=x1) {
	return false;
    }

    int yi = std::lower_bound(row[xi].begin(),row[xi].end(),y1)-row[xi].begin();
    if (yi==(int)row[xi].size()) {
	return false;
    }

    int at = mp[{x1, row[xi][yi]}];

    int dx = x2-x1-1;
    for (int i=LOG-1; i>=0; i--) {
	if (dx>>i&1) {
	    at = par[i][at];
	}
    }

    if (at == 0) return false;
    return Y[at] <= y2;
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0);  cout.tie(0);

    cin>>n>>m>>t;

    for (int i=1; i<=t; i++) {
	cin>>X[i]>>Y[i];
	mp[{X[i],Y[i]}] = i;
	xord.push_back(X[i]);
    }

    sort(xord.begin(),xord.end());
    xord.erase(unique(xord.begin(),xord.end()),xord.end());
    
    for (int i=1; i<=t; i++) {
	int x = lower_bound(xord.begin(),xord.end(),X[i])-xord.begin();
	row[x].push_back(Y[i]);
    }


    for (int i=0; i<(int)xord.size(); i++) {
	sort(row[i].begin(),row[i].end());
    }

    for (int i=0; i<(int)xord.size() - 1; i++) {
	if (xord[i]+1 == xord[i+1]) {
	    for (int y: row[i]) {
		int atId = mp[{xord[i],y}];
		int yto = std::lower_bound(row[i+1].begin(),row[i+1].end(),y)-row[i+1].begin();
		if (yto < (int)row[i+1].size()) {
		    int toId = mp[{xord[i]+1,row[i+1][yto]}];
		    par[0][atId] = toId;
		}

	    }
	}
    }


    for (int j=1; j<LOG; j++) {
	for (int i=1; i<=t; i++) {
	    par[j][i] = par[j-1][par[j-1][i]];
	}
    }

    int q;
    cin>>q;
    
    while (q--) {
	int x1,y1,x2,y2;
	cin>>x1>>y1>>x2>>y2;
	cout<<(solve(x1,y1,x2,y2) ? "Yes\n" : "No\n");
    }
    
    return 0;
}

• Subtask 1: 23 / 23
• Subtask 2: 20 / 20
• Subtask 3: 11 / 11
• Subtask 4: 19 / 19
• Subtask 5: 27 / 27