Cod sursa(job #2084702)

Utilizator avramraresAvram Rares Stefan avramrares Data 9 decembrie 2017 11:35:26
Problema Datorii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.08 kb
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f("datorii.in");
ofstream g("datorii.out");
int i,n,m,a,b,c,arb[15000*4+3],x,a1[15000];

void update (int nod, int a, int b, int poz, int val)
{
    int mij;
    if(a==b)
        arb[nod]=val;
    else
    {
        mij=(a+b)/2;
        if(poz<=mij)
            update(2*nod,a,mij,poz,val);
        else
            update(2*nod+1,mij+1,b,poz,val);
        arb[nod]=arb[2*nod]+arb[2*nod+1];
    }
}

int querry (int nod, int a, int b, int qa, int qb)
{
    int mij,rez1,rez2;
    rez1=0;
    rez2=0;
    if(qa<=a && b<=qb)
    {
        return arb[nod];
    }
    mij=(a+b)/2;
    if(qa<=mij)
        rez1+=querry(2*nod,a,mij,qa,qb);
    if(mij<qb)
        rez2+=querry(2*nod+1,mij+1,b,qa,qb);
    return rez1+rez2;
}

int main()
{
    f>>n>>m;
    for(i=1; i<=n; ++i)
        f>>a1[i],update(1,1,n,i,a1[i]);
    for(i=1; i<=m; ++i)
    {
        f>>c>>a>>b;
        if(c==0)
            a1[a]-=b,update(1,1,n,a,a1[a]);
        else
            g<<querry(1,1,n,a,b)<<'\n';
    }

}