Cod sursa(job #1155144)

Utilizator Daniel3717Aleca Daniel Adrian Daniel3717 Data 26 martie 2014 18:04:47
Problema Datorii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.09 kb
#include <iostream>
#include <fstream>
using namespace std;
#define maxn 15010

int lsb(int nr)
{
    return ((nr)&(-nr));
}

int aib[maxn];
int n;

void update(int pos,int val)
{
    for (int i=pos;i<=n;i+=lsb(i))
        aib[i]+=val;
}

int v[maxn];

int query(int a,int b)
{
    int val=0;
    while (a<=b)
    {
        if (b-lsb(b)<a-1)
        {
            val+=v[b];
            b--;
        }
        else
        {
            val+=aib[b];
            b-=lsb(b);
        }
    }
    return val;
}

int m,i,q,t,val,p;

int main(void)
{
    FILE * f;
    f=fopen("datorii.in","r");
    ofstream g("datorii.out");
    fscanf(f,"%d%d",&n,&m);
    for (i=1;i<=n;i++)
    {
        fscanf(f,"%d",&v[i]);
        update(i,v[i]);
    }
    for (i=1;i<=m;i++)
    {
        fscanf(f,"%d",&q);
        if (q==0)
        {
            fscanf(f,"%d%d",&t,&val);
            update(t,-val);
        }
        if (q==1)
        {
            fscanf(f,"%d%d",&p,&q);
            g<<query(p,q)<<'\n';
        }
    }
    g.close();
    return 0;
}