Submission #967996

#	Time	Username	Problem	Language	Result	Execution time	Memory
967996		LittleOrange	Real Mountains (CCO23_day1problem2)	C++17	10 / 25	1969 ms	61812 KiB

Main

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
const ll mod = 1e6+3;
const ll big = 1e18;
const ll rev2 = 500002;
int main(){
    ios::sync_with_stdio(0);cin.tie(0);
    ll n;
    cin >> n;
    vector<ll> a(n);
    for(ll &i : a) cin >> i;
    vector<ll> b = a;
    sort(b.begin(),b.end());
    b.erase(unique(b.begin(),b.end()),b.end());
    ll ans = 0;
    vector<ll> l = a;
    vector<ll> r = a;
    for(ll i = 1;i<n;i++) l[i] = max(l[i],l[i-1]);
    for(ll i = n-2;i>=0;i--) r[i] = max(r[i],r[i+1]);
    for(ll j = 0;j<b.size()-1;j++){
        ll de = b[j+1]-b[j];
        vector<ll> v;
        for(ll i = 0;i<n;i++){
            if (a[i]<=b[j]&&l[i]>b[j]&&r[i]>b[j]) v.push_back(i);
        }
        if(v.empty()) break;
        //cout << b[j] << ":";
        //for(ll i : v) cout << " " << i;
        //cout << "\n";
        vector<ll> L(n,big),R(n,big);
        for(ll i = 0;i<n;i++) if(a[i]>b[j]) L[i] = R[i] = a[i];
        for(ll i = 1;i<n;i++) L[i] = min(L[i],L[i-1]);
        for(ll i = n-2;i>=0;i--) R[i] = min(R[i],R[i+1]);
        //for(ll i = 0;i<n;i++) cout << L[i] << " \n"[i+1==n];
        //for(ll i = 0;i<n;i++) cout << R[i] << " \n"[i+1==n];
        de%=mod;
        if (v.size()==1){
            ll i = v[0];
            ans += (L[i]+R[i]+b[j])%mod*de%mod+de*(de-1)%mod*rev2%mod;
        }else{
            ll base = (L[v.front()]+R[v.back()]+min(R[v.front()],L[v.back()]))%mod;
            ll cnt0 = v.size()%mod;
            ll cnt = (cnt0*2-3)%mod;
            //cout << base << " " << cnt << " " << de << "\n";
            ans += base*de%mod+cnt*(b[j]*de%mod+de*(de+1)%mod*rev2%mod)%mod+cnt0*(b[j]*de%mod+de*(de-1)%mod*rev2%mod)%mod;
        }
        ans%=mod;
    }
    cout << (ans%mod+mod)%mod << "\n";
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:21:19: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |     for(ll j = 0;j<b.size()-1;j++){
      |                  ~^~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 3 / 3
• Subtask 3: 0 / 3
• Subtask 4: 0 / 3
• Subtask 5: 4 / 4
• Subtask 6: 0 / 5
• Subtask 7: 0 / 4