Submission #860324

#	Time	Username	Problem	Language	Result	Execution time	Memory
860324		naneosmic	Sure Bet (CEOI17_sure)	C++14	100 / 100	79 ms	4824 KiB

sure

#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define float double
#define endl "\n"
using namespace std;
bool f(float a, float b){
    return a>b;
}
int binarySearch(vector<float>&arr, int l, int r, float x){
    if(arr[l]>=x)
        return l;
    if(arr[l+1]>=x)
        return l;
    if(arr[r]<=x)
        return r-1;
    while (l < r) {
        if(l+1==r)
            return l;
        int m = (l+r) / 2;
        if(arr[m]<=x && arr[m+1]>=x)
            return m;
        if (arr[m+1] < x)
            l = m;
        else
            r = m;
    }
    return -1;
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    float n;
    cin>>n;
    vector<float>a(n);
    vector<float>b(n);
    for(float i=0;i<n;i++){
        cin>>a[i]>>b[i];
    }
    sort(a.begin(),a.end(),f);
    sort(b.begin(),b.end(),f);
    vector<float>b_pref;
    float s=0;
    b_pref.push_back(0);
    for(float i=0;i<n;i++){
        s+=b[i];
        b_pref.push_back(s);
    }
    s=0;
    float score=0;
    for(float i=0;i<n;i++){
        s+=a[i];
        float j=binarySearch(b_pref,0,n,s);
        float s1=min(s,b_pref[j])-i-j-1;
        float s2=min(s,b_pref[j+1])-i-j-2;
        score=max(score,s2);
        score=max(score,s1);
    }
    printf("%.4lf",(float)score);
}

• Subtask 1: 20 / 20
• Subtask 2: 40 / 40
• Subtask 3: 40 / 40