Submission #3811075

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Source Code Expand

#include <bits/stdc++.h>
#define FOR(i, begin, end) for(int i=(begin);i<(end);i++)
#define REP(i, n) FOR(i,0,n)
#define IFOR(i, begin, end) for(int i=(end)-1;i>=(begin);i--)
#define IREP(i, n) IFOR(i,0,n)
#define SORT(a) sort(a.begin(), a.end())
#define REVERSE(a) reverse(a.begin(), a.end())
#define Lower_bound(v, x) distance(v.begin(), lower_bound(v.begin(), v.end(), x))
#define Upper_bound(v, x) distance(v.begin(), upper_bound(v.begin(), v.end(), x))
#define int long long
#define INF 1000000000000000000
using namespace std;

#define ANS(f) if(f) cout << "YES" << endl; else cout << "NO" << endl;

typedef vector<int> vec;
typedef vector<vec> mat;
typedef pair<int, int> Pii;

template<typename T>
void readv(vector<T> &a){ REP(i, a.size()) cin >> a[i]; }
void readi(vector<int> &a){ REP(i, a.size()){cin >> a[i]; a[i]--;} }
void debug(mat m){REP(i, m.size()){ REP(j, m[i].size()){ cout << m[i][j] << ","; } cout << endl; }}



signed main(){

    int R, C, N; cin >> R >> C >> N;
    int x1, y1, x2, y2;
    vector<Pii> p1(0), p2(0), p3(0), p4(0);

    REP(i, N){
        cin >> x1 >> y1 >> x2 >> y2;
        if(!(x1 == 0 || x1 == R || y1 == 0 || y1 == C)) continue;
        if(!(x2 == 0 || x2 == R || y2 == 0 || y2 == C)) continue;
        if(x1 == 0) p1.push_back(Pii(y1, i));
        else if(x1 == R) p3.push_back(Pii(y1, i));
        else if(y1 == 0) p4.push_back(Pii(x1, i));
        else if(y1 == C) p2.push_back(Pii(x1, i));
        if(x2 == 0) p1.push_back(Pii(y2, i));
        else if(x2 == R) p3.push_back(Pii(y2, i));
        else if(y2 == 0) p4.push_back(Pii(x2, i));
        else if(y2 == C) p2.push_back(Pii(x2, i));
    }
    vec v(0);
    SORT(p1);
    SORT(p2);
    SORT(p3); REVERSE(p3);
    SORT(p4); REVERSE(p4);
    REP(i, p1.size()) v.push_back(p1[i].second);
    REP(i, p2.size()) v.push_back(p2[i].second);
    REP(i, p3.size()) v.push_back(p3[i].second);
    REP(i, p4.size()) v.push_back(p4[i].second);

    if(v.size() == 0){
        cout << "YES" << endl;
        return 0;
    }

    //REP(i, v.size()) cout << v[i] << endl;
    bool f = false;
    int n = v.size();
    vec s(0);
    REP(i, n){
        if(s.size() == 0 || v[i] != s[s.size() - 1]) s.push_back(v[i]);
        else s.pop_back();
    }
    ANS(s.size() == 0);
    
    return 0;
}

Submission Info

Judge Result