Cod sursa(job #1770075)

Utilizator PletoPletosu Cosmin-Andrei Pleto Data 3 octombrie 2016 18:51:34
Problema Datorii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.87 kb
#include <fstream>

using namespace std;

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

int tree[100001];
int N, M, op;

void update(int idx, int val)
{
    while(idx<=N)
    {
        tree[idx] += val;
        idx += (idx & -idx);
    }
}

int query(int idx)
{
    int sum=0;
    while(idx>0)
    {
        sum += tree[idx];
        idx -= (idx & -idx);
    }
    return sum;
}

int main()
{
    fin>>N>>M;
    for(int i=1; i<=N; ++i)
    {
        int x;
        fin>>x;
        update(i, x);
    }
    for(int i=1; i<=M; ++i)
    {
        int x, a, b;
        fin>>x;
        switch(x)
        {
        case 0:
            fin>>a>>b;
            update(a, -b);
            break;
        case 1:
            fin>>a>>b;
            fout<<query(b) - query(a-1)<<'\n';
            break;
        };
    }
    return 0;
}