Submission #1228756

#	Time	Username	Problem	Language	Result	Execution time	Memory
1228756		kokokai	Rabbit Carrot (LMIO19_triusis)	C++20	100 / 100	167 ms	17664 KiB

triusis

#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define fi first
#define se second
struct fenwick{
    vector<ll> fw;
    int n;
    fenwick(int _n){
        n=_n;
        fw.resize(n+2,0);
    }
    void update(int idx,ll val){
        for(;idx<=n;idx+=idx&(-idx)){
            fw[idx] = max(fw[idx],val);
        }
    }
    ll get(int idx){
        ll res=0;
        for(;idx>0;idx -= idx&(-idx)){
            res=max(res,fw[idx]);
        }
        return res;
    }
};
void solve(){
    ll n,m;
    cin>>n>>m;
    vector<ll> a(n+1);
    vector<ll> tmp;
    tmp.push_back(0);
    for(int i=1;i<=n;i++){
        cin>>a[i];
        a[i]=a[i]-(ll)(i*m);
        tmp.push_back(a[i]);
    }
    map<ll,ll> nen;
    sort(tmp.begin(),tmp.end());
    tmp.erase(unique(tmp.begin(),tmp.end()),tmp.end());
    int cnt=0;
    for(auto v:tmp){
        nen[v]=++cnt;
    }
    fenwick fw(n+2);
    ll ans=0;
    for(int i=n;i>=0;i--){
        int idx=nen[a[i]];
        //cerr<<a[i]<<'\n';
        if(i == 0){
            ans=fw.get(idx)+1;
        }
        fw.update(idx,fw.get(idx)+1);
    }
    cout<<n+1-ans<<'\n';
}
int main(){
    ios::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);

    if(fopen("task.inp", "r")) {
        freopen("task.inp", "r", stdin);
        //freopen("orzdevinwang.out", "w", stdout);
    }
    int tt=1;
    //cin>>tt;
    while(tt--){
        solve();
    }
}

Compilation message (stderr)

triusis.cpp: In function 'int main()':
triusis.cpp:60:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |         freopen("task.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 21 / 21
• Subtask 3: 28 / 28
• Subtask 4: 37 / 37