Submission #653872

#	Time	Username	Problem	Language	Result	Execution time	Memory
653872		true22	Experimental Charges (NOI19_charges)	C++14	0 / 100	7 ms	5332 KiB

charges

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

// short forms // 
#define nl "\n"
#define pb push_back
#define f first
#define s second
#define ll long long int
#define ld long double
#define mp make_pair

#define all(x) x.begin(), x.end()

// debug // 
#define pv(x) for(auto k : x){cout << k << " ";} cout << nl;
#define pp(x) cout << x.f << " " << x.s << nl;
#define bv(x) if (x) cout << "true"; else cout << "false";
#define gp(x, y) x << " " << y 

// loop //
#define FOR(i, a, b) for(ll i = a; i <=b; i++)

// pair // 
typedef pair<ll, ll> pl;

// vector // 
typedef vector<ll> vl;
typedef vector<vl> vvl;    
typedef vector<pl> vp;

// constants // 
const ll INF = 1e17; 
const ll mod = 1e9 + 7;
const ll S = 1e5 + 5;
ll n, siz[S], link[S], eof[S];

ll find(ll a){
    ll st = a;
    while(a != link[a]) a = link[a];
    //path compression
    while(st != link[st]){
        ll tmp = link[st];
        link[st] = a;
        st = tmp;
    }
    return a;
}

bool unite(ll a, ll b){
    a = find(a);
    b = find(b);
    if (a == b) return 0;
    // union by size
    if (siz[a] < siz[b]) swap(a, b);
    siz[a] += siz[b];
    link[b] = a;
    return 1;
}

void set_same(ll a, ll b){ 
    /*
        1) unite the friends
        2) unite the enemies of the friends
        3) copy the link
    */
    a = find(a);
    b = find(b);
    if (siz[a] < siz[b]) swap(a, b);
    unite(a, b);
    if (eof[a] != -1 && eof[b] != -1)
        unite(eof[a], eof[b]);
    if (eof[a] == -1)
        eof[a] = eof[b];
}

void set_op(ll a, ll b){
    /*
        this is symmetric
        the enemy of c1 is united with rep of c1 and vice versa
    */
    a = find(a);
    b = find(b);
    if (eof[a] == -1)
        eof[a] = b;
    else
        unite(eof[a], b);
    if (eof[b] == -1)
        eof[b] = eof[a];
    else
        unite(eof[b], a);
}

bool same(ll a, ll b){
    return (find(a) == find(b));
}

bool attract(ll a, ll b){
    if (eof[a] == -1)
        return 0;
    return same(eof[a], b);
}


void query(ll a, ll b){
    if (same(a, b)){
        cout << 'R' << nl;
        return;
    }
    if (attract(a, b)){
        cout << 'A' << nl;
        return;
    }
    cout << '?' << nl;
}

void solve(){
    FOR(i, 0, S-1){
        link[i] = i;
        siz[i] = 1;
        eof[i] = -1;
    }    
    ll q;
    cin >> n >> q;
    while(q--){
        char t;
        ll a, b;
        cin >> t;
        cin >> a >> b;
        if (t == 'A'){
            set_op(a, b);
        }
        else if (t == 'R'){
            set_same(a, b);
        }
        else{
            if (same(a, b)){
                cout << "R" << nl;
                continue;
            }
            if (same(eof[find(a)], b)){
                cout << "A" << nl;
                continue;
            }
            if (eof[find(a)] == -1){
                cout << "?" << nl;
                continue;
            }
        }
    }
    // cout << find(2) << ' ' << find(4) << nl;
    // cout << eof[find(2)] << nl;
    // bv(same(eof[find(2)], 4));
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);

    #ifndef ONLINE_JUDGE
        freopen("C:/Users/Dell/Documents/Abhineet/Comps/input.txt", "r", stdin);
        freopen("C:/Users/Dell/Documents/Abhineet/Comps/output.txt", "w", stdout);
    #endif

    ll t = 1;
    //cin >> t;
    while(t--){
        
        solve();
    }
    
    return 0;
}

Compilation message (stderr)

charges.cpp: In function 'int main()':
charges.cpp:162:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  162 |         freopen("C:/Users/Dell/Documents/Abhineet/Comps/input.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
charges.cpp:163:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  163 |         freopen("C:/Users/Dell/Documents/Abhineet/Comps/output.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 11
• Subtask 3: 0 / 14
• Subtask 4: 0 / 12
• Subtask 5: 0 / 25
• Subtask 6: 0 / 31