Submission #675049

#	Time	Username	Problem	Language	Result	Execution time	Memory
675049		Ahmed57	San (COCI17_san)	C++14	120 / 120	172 ms	21124 KiB

san

#include<bits/stdc++.h>
using namespace std;
//BIT Fenwick tree
int lim ;
int bit[41]={0};
void add(int e,int v){
    while(e<=lim){
        bit[e]+=v;
        e+=e&-e;
    }
}
long long sum(int e){
    long long res = 0;
    while(e>=1){
        res+=bit[e];
        e -= e&-e;
    }
    return res;
}
//end BIT
long long k,n;
vector<pair<long long,long long>> arr(42);
int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin>>n>>k;
    set<long long> s;
    for(int i = 0;i<n;i++){
        long long a,b;cin>>a>>b;
        s.insert(a);
        arr[i] = {a,b};
    }
    map<long long,long long> compress;
    int z =0;
    for(auto i:s){
        compress[i] = ++z;
    }
    lim = z;
    for(int i = 0;i<n;i++){
        arr[i].first = compress[arr[i].first];
    }
    arr[40]={0,0};
    long long ans = 0;
    vector<pair<long long,long long>> v,w;
    int e = n/2;
    for(long long mask=1;mask<(1<<e);mask++){
        long long s=0,p=40;
        for(long long i=0;i<e;i++){
            if((1<<i)&mask){
                if(arr[i].first>=arr[p].first){
                    s+=arr[i].second;
                }
                else{
                    s=-1;
                    break;
                }
                p=i;
            }
        }
        if(s>=k)ans++;
        if(s!=-1)v.push_back({s,arr[p].first});
    }
    sort(v.begin(),v.end());
    vector<pair<long long,long long>> cd(42);
    for(int i = e;i<n;i++){
        cd[i-e] = arr[i];
    }
    cd[40] = {0,0};
    n-=e;
    for(long long mask=1;mask<(1<<n);mask++){
        long long s=0,p=40,f=-1;
        for(long long i=0;i<n;i++){
            if((1<<i)&mask){
                if(cd[i].first>=cd[p].first){
                    s+=cd[i].second;
                    if(f==-1){
                        f = cd[i].first;
                    }
                }
                else{
                    s=-1;
                    break;
                }
                p=i;
            }
        }
        if(s>=k)ans++;
        if(s!=-1)w.push_back({s,f});
    }
    sort(w.begin(),w.end());
    int d = v.size()-1;
    for(int i = 0;i<w.size();i++){
        while(d>=0&&v[d].first+w[i].first>=k){add(v[d].second,1);d--;}
        ans+=sum(w[i].second);
    }
    cout<<ans;
	return 0;
}

Compilation message (stderr)

san.cpp: In function 'int main()':
san.cpp:91:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   91 |     for(int i = 0;i<w.size();i++){
      |                   ~^~~~~~~~~

• Subtask 1: 24 / 24
• Subtask 2: 24 / 24
• Subtask 3: 24 / 24
• Subtask 4: 24 / 24
• Subtask 5: 24 / 24