Fishers

input/code.cpp: In function 'int main()':
input/code.cpp:60:20: warning: statement has no effect [-Wunused-value]
   60 | #define debug(...) 42
      |                    ^~
input/code.cpp:94:9: note: in expansion of macro 'debug'
   94 |         debug(i, f[i]);
      |         ^~~~~
input/code.cpp:60:20: warning: statement has no effect [-Wunused-value]
   60 | #define debug(...) 42
      |                    ^~
input/code.cpp:104:9: note: in expansion of macro 'debug'
  104 |         debug(from, lim);
      |         ^~~~~
input/code.cpp:60:20: warning: statement has no effect [-Wunused-value]
   60 | #define debug(...) 42
      |                    ^~
input/code.cpp:110:13: note: in expansion of macro 'debug'
  110 |             debug(who, from, to, lim);
      |             ^~~~~

#pragma GCC optimize("O3,unroll-loops")

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

#define int long long
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef long double ld;

string to_string(string s) {
    return '"' + s + '"';
}
 
string to_string(const char* s) {
    return to_string((string) s);
}
 
string to_string(bool b) {
    return (b ? "true" : "false");
}
 
template <typename A, typename B>
string to_string(pair<A, B> p) {
    return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
 
template <typename A>
string to_string(A v) {
    bool first = true;
    string res = "{";
    for (const auto &x : v) {
        if (!first) {
            res += ", ";
        }
        first = false;
        res += to_string(x);
    }
    res += "}";
    return res;
}
 
void debug_out() {
    cerr << endl;
}
 
template <typename Head, typename... Tail>
void debug_out(Head H, Tail... T) {
    cerr << " " << to_string(H);
    debug_out(T...);
}
 
#ifdef LOCAL
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#else
#define debug(...) 42
#endif

const int N = 1e5 + 5;
const int INF = 1e9;

int n, f[2 * N];
int pos[N];
int line[N];
bool vis[N];

signed main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit); // RTE if input wrong datatype

    cin >> n;
    for (int i = 0; i < 2 * n; i++) {
        cin >> f[i];
        if (f[i] > 0) {
            if (vis[f[i]]) { // swap so that the fisher always sit first
                pos[f[i]] = line[f[i]];
                line[f[i]] = i;
                f[pos[f[i]]] = -f[pos[f[i]]];
                f[i] = -f[i];
            } else {
                pos[f[i]] = i;   
            }
        } else {
            line[-f[i]] = i;
            vis[-f[i]] = i;
        }
    }

    for (int i = 0; i < 2 * n; i++) {
        debug(i, f[i]);
    }

    int lim = INF;
    for (int from = 0; from < 2 * n; from++) {
        if (from == lim) {
            int who = -f[from];
            int to = pos[who];
            lim = to + 2*n;
        }
        debug(from, lim);
        if (f[from] > 0) {
            int who = f[from];
            int to = line[who];
            if (to < from) to += 2 * n;
            
            debug(who, from, to, lim);

            if (to > lim) {
                cout << "Yes";
                return 0;
            }
            lim = min(lim, to);
        }
    }
    cout << "No";
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED

Test 28

Verdict: ACCEPTED

Test 29

Verdict: ACCEPTED

Test 30

Verdict: ACCEPTED

Test 31

Verdict: ACCEPTED

Test 32

Verdict: ACCEPTED

Test 33

Verdict: ACCEPTED

Test 34

Verdict: ACCEPTED

Test 35

Verdict: ACCEPTED

Test 36

Verdict: ACCEPTED

Test 37

Verdict: ACCEPTED

Test 38

Verdict: ACCEPTED

Test 39

Verdict: ACCEPTED

Test 40

Verdict: ACCEPTED

Test 41

Verdict: ACCEPTED

Test 42

Verdict: ACCEPTED

Test 43

Verdict: ACCEPTED

Test 44

Verdict: ACCEPTED

Test 45

Verdict: ACCEPTED

Test 46

Verdict: ACCEPTED

Test 47

Verdict: ACCEPTED

Test 48

Verdict: ACCEPTED

Test 49

Verdict: ACCEPTED

Test 50

Verdict: ACCEPTED

Test 51

Verdict: ACCEPTED

Test 52

Verdict: ACCEPTED

Test 53

Verdict: ACCEPTED

Test 54

Verdict: ACCEPTED

Test 55

Verdict: ACCEPTED

Test 56

Verdict: ACCEPTED

Test 57

Verdict: ACCEPTED

Test 58

Verdict: ACCEPTED

Test 59

Verdict: ACCEPTED

Test 60

Verdict: ACCEPTED

Test 61

Verdict: ACCEPTED

Test 62

Verdict: ACCEPTED

Test 63

Verdict: ACCEPTED

Test 64

Verdict: ACCEPTED

Test 65

Verdict: ACCEPTED