Cod sursa(job #2119039)

Utilizator ioana_marinescuMarinescu Ioana ioana_marinescu Data 31 ianuarie 2018 16:03:15
Problema Arbori indexati binar Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.1 kb
#include <bits/stdc++.h>
const int MAX_N = 100005;

using namespace std;

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

int n, m, aib[MAX_N];

void add(int poz, int val)
{
    for(int i=poz; i<=n; i+=i&(-i))
        aib[i]+=val;
}

int sum(int poz)
{
    int sol=0;
    for(int i=poz; i>=1; i-=i&(-i))
        sol+=aib[i];
    return sol;
}

int bs(int val)
{
    int st, dr, mij, s;
    st=1; dr=n;
    while(st<=dr) {
        mij=(st+dr)/2;
        s=sum(mij);
        if(val==s)
            return mij;
        else if(val<s)
            dr=mij-1;
        else
            st=mij+1;
    }
    return -1;
}
int main()
{
    int i, q, a, b, poz, val, x;
    fin>>n>>m;
    for(i=1; i<=n; i++) {
        fin>>x;
        add(i, x);
    }
    for(i=1; i<=m; i++) {
        fin>>q;
        if(q==0) {
            fin>>poz>>val;
            add(poz, val);
        }
        if(q==1) {
            fin>>a>>b;
            fout<<sum(b)-sum(a-1)<<'\n';
        }
        if(q==2) {
            fin>>a;
            fout<<bs(a)<<'\n';
        }
    }
    return 0;
}