Cod sursa(job #1899480)

Utilizator DiClauDan Claudiu DiClau Data 2 martie 2017 19:28:03
Problema Arbori indexati binar Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.52 kb
#include<stdio.h>
using namespace std;
const int N = 100005;
int suma[N], n;
void actualizare (int i, long long val)
{
    while (i <= n)
    {
        suma[i] += val;
        i += (i&-i);
    }
}
long long interog (long long i)
{
    long long s = 0;
    while (i != 0)
    {
        s += suma[i];
        i -= (i&-i);
    }
    return s;
}
long long cautBin (long long a)
{
    int pas = 1 << 16;
    int i = 0;
    while (pas != 0)
    {
        if (i + pas <= n && suma[i + pas] <= a)
        {
            a -= suma[i + pas];
            i += pas;
        }
        pas /= 2;
    }
    if (a == 0)
        return i;
    return -1;
}
int main ()
{
    FILE *in, *out;
    in = fopen ("aib.in", "r");
    out = fopen ("aib.out", "w");
    int m;
    fscanf (in, "%d%d", &n, &m);
    int i, x;
    for (i = 1; i <= n; i++)
    {
        fscanf (in, "%d", &x);
        actualizare (i, x);
    }
    long long a, b;
    for (i = 1; i <= m; i++)
    {
        fscanf (in, "%d", &x);
        if (x == 0)
        {
            fscanf (in, "%lld%lld", &a, &b);
            actualizare (a, b);
        }
        if (x == 1)
        {
            fscanf (in, "%lld%lld", &a, &b);
            fprintf (out, "%d\n", interog(b) - interog(a - 1));
        }
        if (x == 2)
        {
            fscanf (in, "%lld", &a);
            if (a == 0)
                fprintf (out, "-1\n");
            else
                fprintf (out, "%lld\n", cautBin(a));
        }
    }
    return 0;
}