Submission #882706

#	Time	Username	Problem	Language	Result	Execution time	Memory
882706		Ahmed_Solyman	Izbori (COCI22_izbori)	C++14	110 / 110	1963 ms	40908 KiB

Main

/*
In the name of Allah
made by: Ahmed_Solyman
*/
#include <bits/stdc++.h>
#include <ext/rope>
 
using namespace std;
using namespace __gnu_cxx;
#pragma GCC optimize("-Ofast")
#pragma GCC optimize("-O1")
//-------------------------------------------------------------//
typedef long long ll;
typedef unsigned long long ull;
#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define PI acos(-1)
#define lb lower_bound
#define ub upper_bound
#define endl '\n'
#define all(v) v.begin(),v.end()
#define allr(v) v.rbegin(),v.rend()
#define sum_to(n) (n*(n+1))/2
#define pb push_back
#define pf push_front
#define fil(arr,x) memset(arr,x,sizeof(arr))
const ll mod=1e9+7;
int dx[8]={0,1,0,-1,1,1,-1,-1};
int dy[8]={1,0,-1,0,1,-1,-1,1};
//-------------------------------------------------------------//
ll lcm(ll a,ll b)
{
    return (max(a,b)/__gcd(a,b))*min(a,b);
}
void person_bool(bool x)
{
    cout<<(x?"YES":"NO")<<endl;
}
const int N=2e5+5;
int n,arr[N];
ll solve(int l,int r){
    if(l>r){
        return 0;
    }
    if(l==r){
        return 1;
    }
    int mid=l+r>>1;
    ll ret=0;
    set<int>s;
    map<int,int>fr;
    for(int i=mid;i<=r;i++){
        fr[arr[i]]++;
        if(fr[arr[i]]*2>i-mid+1){
            s.insert(arr[i]);
        }
    }
    fr.clear();
    for(int i=mid;i>=l;i--){
        fr[arr[i]]++;
        if(fr[arr[i]]*2>mid-i){
            s.insert(arr[i]);
        }
    }
    for(auto x:s){// atmost log n numbers
        fr.clear();
        int prefix=0;
        fr[prefix]++;
        for(int i=l;i<mid;i++){
            prefix+=(arr[i]==x?1:-1);
            fr[prefix]++;
        }
        int sz=(r-l+1);
        for(int i=-sz;i<=sz;i++){
            fr[i]+=fr[i-1];
        }
        for(int i=mid;i<=r;i++){
            prefix+=(arr[i]==x?1:-1);
            ret+=fr[prefix-1];
        }
    }
    return ret+solve(l,mid-1)+solve(mid+1,r);
}
int main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    #ifndef ONLINE_JUDGE
///    freopen("input.in", "r", stdin);
///    freopen("output.out", "w", stdout);
    #endif
    fast
    cin>>n;
    for(int i=0;i<n;i++){
        cin>>arr[i];
    }
    cout<<solve(0,n-1)<<endl;
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'll solve(int, int)':
Main.cpp:47:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   47 |     int mid=l+r>>1;
      |             ~^~

• Subtask 1: 10 / 10
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 70 / 70