Cod sursa(job #2426091)

Utilizator anamariatoaderAna Toader anamariatoader Data 26 mai 2019 10:51:19
Problema Arbori indexati binar Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.09 kb
#include <fstream>
//codeforces

using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");

int n,m,i,aib[100005],v[100005],t,a,b;

int query(int x){
    int s=0;
    while(x>0){
        s+=aib[x];
        x=x-(x&(-x));
    }
    return s;
}

void update(int x, int v){
    while(x<=n){
        aib[x]+=v;
        x+=(x&(-x));
    }
}

int caut_binar(int a){
    int st=1,dr=n,mij,sol=0;
    while(st<=dr){
        mij=(st+dr)/2;
        if(query(mij)<a)
            st=mij+1;
        else{
            sol=mij;
            dr=mij-1;
        }
    }
    return sol;
}

int main()
{
    fin>>n>>m;
    for(i=1;i<=n;i++){
        fin>>v[i];
        update(i,v[i]);
    }
    for(i=1;i<=m;i++){
        fin>>t;
        if(t==0){
            fin>>a>>b;
            update(a,b);
        }
        else if(t==1){
            fin>>a>>b;
            int sum=query(b)-query(a-1);
            fout<<sum<<'\n';
        }
        else{
            fin>>a;
            int k=caut_binar(a);
            fout<<k<<'\n';
        }
    }
    return 0;
}