Submission #914293

#	Time	Username	Problem	Language	Result	Execution time	Memory
914293		Amr	Joker (BOI20_joker)	C++14	14 / 100	114 ms	856 KiB

Joker

#include <bits/stdc++.h>
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef long double ld;
#define S second
#define F first
#define all(x) (x).begin(),(x).end()
#define sz size()
#define Yes cout << "YES" << endl
#define No cout << "NO" << endl
#define pb(x) push_back(x);
#define endl '\n'
#define fast ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
const int N=2e3+7;
ll INF=INT_MAX,mod=1e9+7;
int TT=1;
ll power(ll x, unsigned int y)
{
    ll res = 1;
    x = x; // % mod;
    if (x == 0) return 0;
    while (y > 0)
    {
        if (y & 1) res = (res*x)  ; // % mod;
        y = y>>1;
        x = (x*x) ; // % mod;
    }
    return res;
}
vector<ll> v[N];
ll dp[N];
ll vis[N];
pair<ll,ll> a[N];
bool dfs(ll x, ll par)
{
bool cnt = 1;
    if(vis[x]==cnt)
    {
        if(dp[x]%2==dp[par]%2) return 1;
        return 0;
    }
    dp[x] = dp[par]+1;
    vis[x] = cnt;
    bool ok = 0;
    for(int i = 0; i < v[x].sz; i++)
        if(v[x][i]!=par) ok|=dfs(v[x][i],x);
        return ok;
}
ll n , m , q;
void solve()
{
    cin >> n >> m >> q;
    for(int i = 1; i <= m; i++)
    {
        ll x, y; cin >> x >> y;
        a[i] = {x,y};
    }
    while(q--)
    {
        ll l , r; cin >> l >> r;
        for(int i = 1; i < N; i++) v[i].clear();
        dp[0] = 0;
        memset(vis,0,sizeof vis);
        for(int i = 1; i <= m; i++)
        {
            if(i<l||i>r)
            {
                v[a[i].F].push_back(a[i].S);
                v[a[i].S].push_back(a[i].F);
            }
        }
        bool ok = 0;
        for(int i = 1; i <= n; i++)
        {
            if(vis[i]==0)
                ok|=dfs(i,0);
        }
        if(ok) cout << "YES" << endl; else cout << "NO" << endl;
    }

}
int main(){
    //freopen("friday.in","r",stdin);
    //freopen("friday.out","w",stdout);
    fast;
  //  cin >> TT;
    while(TT--)
        solve();

    return 0;
}

Compilation message (stderr)

Joker.cpp: In function 'bool dfs(ll, ll)':
Joker.cpp:46:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   46 |     for(int i = 0; i < v[x].sz; i++)
      |                      ^
Joker.cpp:46:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   46 |     for(int i = 0; i < v[x].sz; i++)
      |     ^~~
Joker.cpp:48:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   48 |         return ok;
      |         ^~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 8 / 8
• Subtask 3: 0 / 25
• Subtask 4: 0 / 10
• Subtask 5: 0 / 22
• Subtask 6: 0 / 29