Source Code
#ifndef LOCAL
#pragma GCC optimize("Ofast")
#pragma GCC target("avx,avx2,fma")
#pragma GCC optimization ("unroll-loops")
#endif
#include "bits/stdc++.h"
#include <ext/pb_ds/assoc_container.hpp> // Common file
#include <ext/pb_ds/tree_policy.hpp> // Including tree_order_statistics_node_update
#include <ext/pb_ds/detail/standard_policies.hpp>
using namespace std;
using namespace __gnu_pbds;
#define sim template < class c
#define int long long
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
  enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
~debug() { cerr << '\n'; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (auto it = d.b; it != d.e; ++it)
    *this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
#define fastio ios_base::sync_with_stdio(false);cin.tie(0);
typedef tree< pair<int,int>, null_type, less<pair<int,int> >, rb_tree_tag, tree_order_statistics_node_update> ordered_set;
typedef long long ll;
#define sz(x) (int)(x).size()
const ll MOD = 1e9 + 7 ;
const ll N = 2e5 + 10 ;
const ll INF = 1e18 + 10 ;
#define endl '\n'
// remove above line when interactive
/*
Some Notes:

// Cards
even even
odd odd
even odd

my last move and the cur is even
my last move and the cur is odd


*/
signed main(){
    fastio
    int n , k , m;
    cin >> n >> k >> m;
    vector<int> a(n), b(n);
    bool bothEven = 0;
    bool bothOdd = 0;
    bool other = 0;
    int cur = 0;
    for (int i = 0; i < n; i++) {
    	cin >> a[i] >> b[i];
    	a[i] %= 2;
    	b[i] %= 2;
    	if (a[i] && b[i]) bothOdd = 1;
    	else if (!a[i] && !b[i]) bothEven = 1;
    	else other = 1;
    	cur += a[i];
    }
    cur %= 2;
    int lastMove = k % 2 == 0 ? 2 : 1;
    if (bothOdd && bothEven && other) {
    	cout << lastMove << endl;
    }
    else if ((bothOdd || bothEven) && other) {
    	cout << lastMove << endl;
    }
    else if (!other) {
    	if (lastMove == 1) {
    		if (cur == m) {
    			cout << lastMove << endl;
    		}
    		else cout << (lastMove ^ 3) << endl;
    	}
    	else {
    		if (cur == m) {
    			cout << lastMove << endl;
    		}
    		else cout << (lastMove ^ 3) << endl;
    	}
    }
    else {
    	cout << lastMove << endl;
    }

    return 0; 
}
Copy
Cliffs of Dover Ranger
GNU G++17
43 ms
5.6 MB
Wrong Answer