Cod sursa(job #3150977)

Utilizator Nasa1004Ema Nicole Gheorghe Nasa1004 Data 19 septembrie 2023 11:46:29
Problema Arbori indexati binar Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.3 kb
#include <fstream>

using namespace std;

ifstream cin("aib.in");
ofstream cout("aib.out");

int bit[100002], n, m;
void update(int i, int val)
{
    while(i <= n)
    {
        bit[i] += val;
        i += i & -i;
    }
}
int prefixSum(int i)
{
    int sum = 0;
    while(i > 0)
    {
        sum += bit[i];
        i -= i & -i;
    }
    return sum;
}
int rangeSum(int i, int j)
{
    return prefixSum(j) - prefixSum(i - 1);
}
int main()
{
    int ok, a, b;
    cin >> n >> m;
    for(int i = 1; i <= n; i++)
    {
        cin >> a;
        update(i, a);
    }
    for(int i = 1; i <= m; i++)
    {
        int minn = 100002;
        cin >> ok >> a;
        if(ok != 2)
            cin >> b;

        if(ok == 0)
            update(a, b);
        else if(ok == 1)
            cout << rangeSum(a, b) << '\n';
        else if(ok == 2)
        {
            int l = 1, s = 0;
            for (int r = 1; r <= n; r++)
            {
                s = rangeSum(l, r);

                while (s > a)
                {
                    s -= rangeSum(l, l);
                    l++;
                }
                if(s == a && r - l + 1 < minn)
                    minn = r - l + 1;
            }
            cout << minn << '\n';
        }

    }
    return 0;
}